I transplanted about 70 seedlings into 1-gallon pots recently. I don't have much topsoil so I used rotting wood chips in the bottom half and
compost in the top half, with a thin layer of peat moss on the top. So far the plants seem happy, and there a lot of mushrooms sprouting up.
So yes I think hugelkultur in a pot would work as long as the wood is fairly well decomposed.