I have 400 amp service main panel. One subpanel in same building. Between panels do wires have to be in conduit, if
They are in 2x6 wall and 2x12 sealing?

2nd panel in another building 50' away, no metal bonding between them. Am I right with having separate ufer in this building for the grounding?

I have 400 amp service main panel. One subpanel in same building. Between panels do wires have to be in conduit, if
They are in 2x6 wall and 2x12 sealing? Not unless your local codes require it.




2nd panel in another building 50' away, no metal bonding between them. Am I right with having separate ufer in this building for the grounding?A grounding electrode is required at a detached structure with a sub-panel. A ufer is the best type of electrode.

This has nothing to do with the required equipment ground that you must run with the feeder conductors.

Equipment grounding and grounding electrodes are two completely separate things with two completely separate functions.
Grounding electrodes have nothing to do with clearing faults and tripping breakers on the secondary (120/240v) side.