Note added in proof, I am wondering if this issue has something to do with the separate forcefield optimisation issue noted by avervit (Faulty geometry optimisation in the new build) as for themac excecutable also only the LJ forcefield results in the moving of atoms. With all other forcefield, when used directy via the Optimize Geometry option instead of via openbabel, the same happens as for xtb, exacly nothing.