Disclaimer: this issue probably only bothers VR-users! And maybe only me.
FOUND IT! Damn this might be the happiest day in my AC-mod-fixing-life and the solution is so stupidly simple it's almost ironic.
[MESH_ADJUSTMENT_...]
MESHES = A,B,C
MOVE_TO = COCKPIT_HR
If you got the Lamborghini Countach 2022 from MNBA you can test it out by placing this code somewhere in the ext-config.ini
[MESH_ADJUSTMENT_...]
MESHES = LOD1_0_6_5, LOD1_0_6_2, LOD1_0_6_3, LOD1_1_6_7, LOD1_1_6_6, LOD1_0_6_5.002, LOD1_0_4_2_ncl1_1, LOD1_1_6_6.002, LOD1_1_6_7.002
MOVE_TO = COCKPIT_HR
Before (look at the carbon panel on the door):
View attachment 1324984
And after code to ext_config.ini:
View attachment 1324985
( It's already apparent on a screenshot. When moving in game, seeing the asphalt texture and colorfull kerbstones run across the reflective carbon is...dealbreaking. At least for me.)
N.B. This "fix" will most likely break the door-animations and if it does, it scatteres the door-objects all over the place (fix by deleting those door.ksanim files from the animation folder, no more door-animations is the compromise to make). Also it will probably only work if the car-model already has a COCKPIT_HR node/dummy.
You might think it sounds like a very specific problem, but you'd be suprised how many of the "better looking" car mods have this issue-combination: encrypted/has COCKPIT_HR/doesn't have the interior-side of the door-objects placed inside of COCKPIT_HR.
For example almost all of MNBA's mods have this issue, just to name one, but there are a lot more modders/groups that consequently build cars this way.
If you'd also count the unecrypted mods with the same issue, I think we're talking almost half of the car-mods that are available in AC.
Anyway, enough rambling, I'm happy and wanted to share since I asked this question multiple times in this thread and never got the answer. So, maybe this info is indeed new and helps someone else out as well.