I do both but after trimming more weed than I care to imagine, I think it's easiest and definitely the fastest to do it wet. Espeically if you are giving it a really close trim. I've even won a case of beer in a bet over it
For the outdoor patch though it's hack off the shade leaves and a light trim when green, sometimes while the plant is still standing, then it's dried and gets a final clean up.
The problem is that when it's been dried and hung the smaller bud leaves can stick to the bud, meaning you need to get the scissors in there and take care you don't hack off any of the good stuff. It takes way more care, attention and concentration. Which lets face it, because 99% the time trimming is done when stoned on trim hash, concentration is a thing.
When green, you can almost shear the buds like a sheep, take the shade leaves off for the compost, then shave the buds closer the next round.