See title. Will mods need to be updated for the 1.6 navmesh fix to take effect, or is it a global thing that will fix all mods affected?

Self correcting. They'll just work.

Hmm ok. I'm still having CTDs with certain quest mods enabled while using 1.6. I'm guessing the issues aren't navmesh related, then.

Most likely not. There's plenty of stuff mods can crash with