Your options are
1) Manually tune the system to reduce the voltage applied.
2) Disable MCE and revert to stock
3) Upgrade or check your current cooling solution is adequate
Those temps are quite high for games alone. Assassins Creed Origins is proving more noticeable as the game is fairly CPU intensive, as well as the DRM solution putting a load on some cores.
13900KS / 8000 CAS36 / ROG APEX Z790 / ROG TUF RTX 4090