I gave up with the cross under and I just go for the old CS1 combo dash after belial edge 5DD 22c works for me. When I do the cross unders I use 5B 6A HJC jC jD jD 214C 5DD 623D 236C 214D
I was messing around in training mode after seeing a combo video and found this combo
2C (FC) 6B 5C 6C (DC) 6B 5C 5D1 214B 22C (RC) 6C (DC) 6B 5C 5D1 214D 5C (HJC) jC jD j214C dash 5DD 22C