In my experience, grip is only ever an issue in the snatch, and it's really a product of the extreme angle you're attaching yourself to the bar. So in that sense, the typical grip work doesn't transfer much at all (e.g. farmer's walk, hanging from bar) unless you can mimic that angle - which you can do fairly well with farmers' walk implements like dumbbells by tilting them.
That said, the other problem is that static holds of that nature are training grip stamina more than strength. How long do you have to hold onto a bar to snatch it? 2 seconds max?
The issue is maintaining a tight grip while accelerating a heavy load - very different from just hanging onto something and walking around. That being the case, I think a more effective option is doing some kind of pull without straps - for example, a short pull off blocks with a snatch grip - working that acceleration. Don't bring it back down - drop it - because that lowering part is what's going to destroy your hands and very quickly limit how much you can do and how many times.
Like others have already said, this is not something you want to do on a very frequent or high-volume basis. I would try maybe 5-15 total reps 1x/week after workouts for a few weeks and see what happens.