Ok I finally got it compiled in VS19 using compiler 14.22.27905 and SDK 10.0.18362.0. Instead of building chaos demo’s ue4 solution, I built UE4 SLN from GitHub source after rerunning setup and generate bat. Chaos clothes, solver etc enabled without trouble but haven’t started using them yet.
The b compile chaos also needs to be in ue4.editor.target.ini like this,
Edit- Grr lighmass still needs to be built separately.