sibby🎉 As of writing, five of our minecraft mods support all loaders on 1.20.1, and the remaining 8 mods support quilt and fabric. They're all compiled from quilt toolchain projects against purely the fabric-namespaced QFAPI modules, allowing this.
Yes, including Switchy - the "I've asked the server admin to add Switchy to their server but they're not confident swapping the modpack from fabric to quilt" problem is solved.
Switchy on forge via connector should work when server translations api and owo-lib work on forge - so hopefully 1.20.2.