I have had a good look at feats and the PHB feats are almost all replaced in the UA document. The ones that are not have been depreciated in one way or another.If you don't want your character to have feats then they can just take the repeatable Ability Score Improvement 4th level feat. And there's nothing preventing the old backgrounds working - so you never need to take a non-ASI feat regardless of which version you are using. So the legacy versions still work.
The question is about the legacy versions of the current feats. But that's mostly errata.