FBufferWriter Swap byte occur in source data

I want to write data to buffer with FBufferWriter. But it swap the source data not the buffer data.
I found out the method ‘ByteOrderSerialize’ in FArchive swap the source data actually.
So I try to create a new Writer inherit from FArchive and override this method. Unfortunately, it is’n an virtual method.
Is there any other solution to slove this? thanks a lot!

FArchive source code:

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