Convert .mov to HEVC H265 Final Cut Pro through COMPRESSOR

Hi ,
I have some video clips with the clear alpha channel, done in MOV and not supported by iOS 13 iPhone, I’ve heard recently that with new H265 HEVC format it is possible to have these clips run in I phone with preserved clear back ground The problem facing is actually is conversion of .mov to HEVC keeping rgb and alpha. Apple forums say it is ONLY possible to convert this using Final Cut Pro through compressor .
I was want to know if you can help me out with conversion of these clips? Each clipis about 12-15 secs