Hi
in ascent guidance, when you choose Stock-style GravityTurn, Limit throttle to [%] and Limit acceleration to [m/s²] are the same.
when you change one, the other take the same value. ....
and limit acceleration doesn t work

Old issue I see. I have pretty much the same thing with throttle and acceleration values linked in KSP v1.12.3. One thing I did check is that the problem pops up immediately in a new install of v1.12.3 that's modded with only MJ2 and its Module Manager dependency. I'm going to try downloading MJ2 and manually installing it. I use CKAN for virtually all mod installs.