Iceshrimp.NET has a section titled "FEPs we intend to support in the future" in their FEDERATION.md:
Streams: "Fediverse FEPs we will not ever support"
NodeBB has a similar page in their documentation where position towards various FEPs is indicated using words "positive", "neutral", "defer", and "negative":
https://docs.nodebb.org/activitypub/fep/
I think this is a good practice.