Paragraph style copy/renaming

I have a bunch of document that has X Heading Y (BT Heading 1, BT Heading 2, BT Heading 3) format instead of Heading 1, Heading 2, Heading 3)... so they won't show up in cross reference / heading.

Is there a way to write a VBA to rename these, or to copy the format from X Heading Y to Heading Y ?

Thanks so much in advance!

Searched online but couldn't find any related articles.

Timothy Rylatt is right, you can refer to his point and implement it, the following code I implemented is a similar one, you can try first:

Sub Paragraph_style_copy_renaming()
    Dim destStyleName, sourceStyleName, d As Word.Document, e, i
    destStyleName = Array("BT Heading 1", "BT Heading 2", "BT Heading 3")
    sourceStyleName = Array(WdBuiltinStyle.wdStyleHeading1, WdBuiltinStyle.wdStyleHeading2, WdBuiltinStyle.wdStyleHeading3)
    Set d = ActiveDocument
    For Each e In sourceStyleName
        UpdateStyle2RangeStyle d.Styles(e), d.Styles(destStyleName(i))
        i = i + 1
    Next e
    i = 0
    With d.Range.Find
        .ClearAllFuzzyOptions
        .ClearFormatting
        For Each e In destStyleName
            .Style = d.Styles(e)
            .Wrap = wdFindContinue
            .Replacement.Style = sourceStyleName(i)
            .Execute Replace:=wdReplaceAll
            i = i + 1
        Next e
    End With
End Sub


Sub UpdateStyle2RangeStyle(sourceStyle As Style, destStyle As Style)
    sourceStyle.AutomaticallyUpdate = destStyle.AutomaticallyUpdate
    With sourceStyle.Font
        .NameFarEast = destStyle.Font.NameFarEast
        .NameAscii = destStyle.Font.NameAscii
        .NameOther = destStyle.Font.NameOther
        .Name = destStyle.Font.Name
        .Size = destStyle.Font.Size
        .Bold = destStyle.Font.Bold
        .Italic = destStyle.Font.Italic
        .Underline = destStyle.Font.Underline
        .UnderlineColor = destStyle.Font.UnderlineColor
        .StrikeThrough = destStyle.Font.StrikeThrough
        .DoubleStrikeThrough = destStyle.Font.DoubleStrikeThrough
        .Outline = destStyle.Font.Outline
        .Emboss = destStyle.Font.Emboss
        .Shadow = destStyle.Font.Shadow
        .Hidden = destStyle.Font.Hidden
        .SmallCaps = destStyle.Font.SmallCaps
        .AllCaps = destStyle.Font.AllCaps
        .Color = destStyle.Font.Color
        .Engrave = destStyle.Font.Engrave
        .Superscript = destStyle.Font.Superscript
        .Subscript = destStyle.Font.Subscript
        .Scaling = destStyle.Font.Scaling
        .Kerning = destStyle.Font.Kerning
        .Animation = destStyle.Font.Animation
        .DisableCharacterSpaceGrid = destStyle.Font.DisableCharacterSpaceGrid
        .EmphasisMark = destStyle.Font.EmphasisMark
        .Ligatures = destStyle.Font.Ligatures
        .NumberSpacing = destStyle.Font.NumberSpacing
        .NumberForm = destStyle.Font.NumberForm
        .StylisticSet = destStyle.Font.StylisticSet
        .ContextualAlternates = destStyle.Font.ContextualAlternates
    End With
    With sourceStyle.ParagraphFormat
        .LeftIndent = destStyle.ParagraphFormat.LeftIndent
        .RightIndent = destStyle.ParagraphFormat.RightIndent
        .SpaceBefore = destStyle.ParagraphFormat.SpaceBefore
        .SpaceBeforeAuto = destStyle.ParagraphFormat.SpaceBeforeAuto
        .SpaceAfter = destStyle.ParagraphFormat.SpaceAfter
        .SpaceAfterAuto = destStyle.ParagraphFormat.SpaceAfterAuto
        .LineSpacingRule = destStyle.ParagraphFormat.LineSpacingRule
        .LineSpacing = destStyle.ParagraphFormat.LineSpacing
        .Alignment = destStyle.ParagraphFormat.Alignment
        .WidowControl = destStyle.ParagraphFormat.WidowControl
        .KeepWithNext = destStyle.ParagraphFormat.KeepWithNext
        .KeepTogether = destStyle.ParagraphFormat.KeepTogether
        .PageBreakBefore = destStyle.ParagraphFormat.PageBreakBefore
        .NoLineNumber = destStyle.ParagraphFormat.NoLineNumber
        .Hyphenation = destStyle.ParagraphFormat.Hyphenation
        .FirstLineIndent = destStyle.ParagraphFormat.FirstLineIndent
        .OutlineLevel = destStyle.ParagraphFormat.OutlineLevel
        .CharacterUnitLeftIndent = destStyle.ParagraphFormat.CharacterUnitLeftIndent
        .CharacterUnitRightIndent = destStyle.ParagraphFormat.CharacterUnitRightIndent
        .CharacterUnitFirstLineIndent = destStyle.ParagraphFormat.CharacterUnitFirstLineIndent
        .LineUnitBefore = destStyle.ParagraphFormat.LineUnitBefore
        .LineUnitAfter = destStyle.ParagraphFormat.LineUnitAfter
        .MirrorIndents = destStyle.ParagraphFormat.MirrorIndents
        .TextboxTightWrap = destStyle.ParagraphFormat.TextboxTightWrap
        .CollapsedByDefault = destStyle.ParagraphFormat.CollapsedByDefault
        .AutoAdjustRightIndent = destStyle.ParagraphFormat.AutoAdjustRightIndent
        .DisableLineHeightGrid = destStyle.ParagraphFormat.DisableLineHeightGrid
        .FarEastLineBreakControl = destStyle.ParagraphFormat.FarEastLineBreakControl
        .WordWrap = destStyle.ParagraphFormat.WordWrap
        .HangingPunctuation = destStyle.ParagraphFormat.HangingPunctuation
        .HalfWidthPunctuationOnTopOfLine = destStyle.ParagraphFormat.HalfWidthPunctuationOnTopOfLine
        .AddSpaceBetweenFarEastAndAlpha = destStyle.ParagraphFormat.AddSpaceBetweenFarEastAndAlpha
        .AddSpaceBetweenFarEastAndDigit = destStyle.ParagraphFormat.AddSpaceBetweenFarEastAndDigit
        .BaseLineAlignment = destStyle.ParagraphFormat.BaseLineAlignment
    End With
    sourceStyle.NoSpaceBetweenParagraphsOfSameStyle = destStyle.NoSpaceBetweenParagraphsOfSameStyle
    sourceStyle.ParagraphFormat.TabStops.ClearAll
    With sourceStyle.ParagraphFormat
        With .Shading
            .Texture = destStyle.ParagraphFormat.Shading.Texture
            .ForegroundPatternColor = destStyle.ParagraphFormat.Shading.ForegroundPatternColor
            .BackgroundPatternColor = destStyle.ParagraphFormat.Shading.BackgroundPatternColor
        End With
        .Borders(wdBorderLeft).LineStyle = destStyle.ParagraphFormat.Borders(wdBorderLeft).LineStyle
        .Borders(wdBorderRight).LineStyle = destStyle.ParagraphFormat.Borders(wdBorderRight).LineStyle
        .Borders(wdBorderTop).LineStyle = destStyle.ParagraphFormat.Borders(wdBorderTop).LineStyle
        .Borders(wdBorderBottom).LineStyle = destStyle.ParagraphFormat.Borders(wdBorderBottom).LineStyle
        With .Borders
            .DistanceFromTop = destStyle.ParagraphFormat.Borders.DistanceFromTop
            .DistanceFromLeft = destStyle.ParagraphFormat.Borders.DistanceFromLeft
            .DistanceFromBottom = destStyle.ParagraphFormat.Borders.DistanceFromBottom
            .DistanceFromRight = destStyle.ParagraphFormat.Borders.DistanceFromRight
            .Shadow = destStyle.ParagraphFormat.Borders.Shadow
        End With
    End With
    sourceStyle.LanguageID = destStyle.LanguageID
    sourceStyle.NoProofing = destStyle.NoProofing
    sourceStyle.LanguageID = destStyle.LanguageID
    sourceStyle.NoProofing = destStyle.NoProofing
    sourceStyle.Frame.Delete
End Sub

I'd like to find out the argument of the Application.CommandBars.ExecuteMso to do this update style mission just like following Tim's answer to easily and accurately accomplish with agility, however, I couldn't find it. Just found something like it(Options.UpdateStyleListBehavior property), but should be not this. Thus the only way to achieve it was to record a macro to simulate and reproduce all the relevant properties and methods. So if there are any omissions, please take note of them.

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