Uploading music from Mac mini to iPhone 16e

I have no desire to sync my entire music collection to my iPhone. I just want to be able to copy a select number of files. I had been successful months ago in uploading some wav files, but I want to replace them with smaller AAC versions. I forget how I initially got the wav files into the Music app on the iPhone, but instructions say that I need to first have the files in the Music app on my Mac mini. However, the Music app on the Mac mini refuses to accept AAC files.

Is it at all possible to avoid having to involve the Music app on the Mac mini? This seems more complicated than it should be, to me. Thanks.