If I take a file made by GoldWave with WAV tag that shows fine in MediaMonkey V4.1.3.1708 and save it in Mp3tag v2.83i (with default config), the tag fields fail to show in MediaMonkey.
I tried working around by changing the config inc. Mp3tag Options Tag Mpeg despite that Help says this should not affect WAV, and I got a result that didn't show the problem and had a different encoding: