Yes two instances of MMDVM_Bridge:
bm tg <->MB_bm<->MB_xlx<->XLX ref
Point first MB_BM to BM and second MB_XLX point to XLX reflector. On DVSwitch.ini cross DMR port.
If you want XLX <-> YSF you can do the same as you mentioned one instance of MB in another project which I prefer.