Converting String Date to DateTimePST(String) and DateTimeLocal(String) using Offset?

I have three parameters, UTCTime and two offsets all three as strings, I need to convert them as below

Input: 
    String UTCTime = "2020-09-29 16:06:00";
    String PSTOffset = "-07:00";
    String LocalOffset = "-04:00";

Output Expected:
        LocalTime = "2020-09-29 12:06:00"
        PSTTime = "2020-09-29 09:06:00"

I tried doing something like this

    OffsetDateTime OffsetLocalTime = OffsetDateTime.parse(String.format("%sT%sZ",UTCTime.split(" ")[0],UTCTime.split(" ")[1]));
    OffsetLocalTime = OffsetLocalTime.withOffsetSameInstant(ZoneOffset.of(LocalOffset));

    OffsetDateTime OffsetPSTTime = OffsetDateTime.parse(String.format("%sT%sZ",UTCTime.split(" ")[0],UTCTime.split(" ")[1]));
    OffsetPSTTime = OffsetPSTTime.withOffsetSameInstant(ZoneOffset.of(PSTOffset));

    String LocalTime = String.format("%s %s",OffsetLocalTime.toString().substring(0,OffsetLocalTime.toString().lastIndexOf('-')).split("T")[0],OffsetLocalTime.toString().substring(0,OffsetLocalTime.toString().lastIndexOf('-')).split("T")[1]);
    String PSTTime = String.format("%s %s",OffsetPSTTime.toString().substring(0,OffsetPSTTime.toString().lastIndexOf('-')).split("T")[0],OffsetPSTTime.toString().substring(0,OffsetPSTTime.toString().lastIndexOf('-')).split("T")[1]);

    System.out.println("OffsetLocalTime: "+OffsetLocalTime);
    System.out.println("OffsetPSTTime: "+ OffsetPSTTime);

    System.out.println("LocalTime: "+ LocalTime);
    System.out.println("PSTTime: "+ PSTTime);

    Actual Output:

    OffsetLocalTime: 2020-09-29T12:06-04:00
    OffsetPSTTime: 2020-09-29T09:06-07:00
    LocalTime: 2020-09-29 12:06
    PSTTime: 2020-09-29 09:06

I am missing out seconds and this seems to be an inefficient way beacuse i do not need 'T' or offset in my output and i am getting rid of them. I am not sure if this question is already asked. Any help is appreciated.

Since the given date-time string, 2020-09-29 16:06:00 does not have zone-offset information, it needs to be first parsed into LocalDateTime and then the LocalDateTime can be converted into OffsetDateTime.

Do it as follows:

import java.time.LocalDateTime;
import java.time.OffsetDateTime;
import java.time.ZoneOffset;
import java.time.format.DateTimeFormatter;

public class Main {
	public static void main(String[] args) {
		// Define the formatter
		DateTimeFormatter formatter = DateTimeFormatter.ofPattern("uuuu-MM-dd HH:mm:ss");

		// Given date-time
		String localTimeUTC = "2020-09-29 16:06:00";

		// Get OffsetDateTime from the given date-time string
		OffsetDateTime odtUTC = LocalDateTime.parse(localTimeUTC, formatter).atOffset(ZoneOffset.UTC);

		// OffsetDateTime with an Zone-Offset of -7 hours
		OffsetDateTime odtAtOffsetMinus7Hours = odtUTC.withOffsetSameInstant(ZoneOffset.ofHours(-7));
		System.out.println(odtAtOffsetMinus7Hours.format(formatter));

		// OffsetDateTime with an Zone-Offset of -4 hours
		OffsetDateTime odtAtOffsetMinus4Hours = odtUTC.withOffsetSameInstant(ZoneOffset.ofHours(-4));
		System.out.println(odtAtOffsetMinus4Hours.format(formatter));
	}
}

Output:

2020-09-29 09:06:00
2020-09-29 12:06:00

Note: Instead of using ZoneOffset.ofHours(-7), you can also use ZoneOffset.of("-07:00") depending on what (number/string) you have got to work with.