There is not a comparable Lemmy enhancement suite AFAIK, though some of the RES features exist in different Lemmy mobile apps and web frontends. For example, the Thunder and Summit mobile apps support user tags.

If you want something browser-based, poke around in the various alternative frontends and see if they fit what you are looking for.

https://a.lemmy.world/ - Alexandrite UI
https://photon.lemmy.world/ - Photon UI
https://m.lemmy.world/ - Voyager mobile UI
https://old.lemmy.world/ - A familiar UI

There is also PieFed, which is a Lemmy-compatible platform and also offers some different features in its frontend.

Piefed allows you to tag users natively https://piefed.fediverse.observer/list

Er... RES. Not RIF. I dumb. 🤦‍♂️

Old.lemmy.world does integrate some of the RES features into the base UI.
I haven't used it recently so I am unsure if the tagging function is there.