Rosetta on Mac was obviously impressive. There was also impressive Arm->Intel translation in the mobile ecosystem at one time.

One reason it works surprisingly well on modern systems is how much is offloaded to the GPU. You aren't going to get great power optimization or anything without it being truly native though.

There are games which are CPU limited though, and it will be interesting how those do. Curiously those also tend to be in engines with Arm support already.