For BLD, I'm using Y perm for corners (shooting from UBL to RDF) and I'm trying to switch from Old Pochmann edges to M2. When their are an odd number of Y perms (so parity I guess...) what alg do you use to restore the swapped edges? I do corners first then edges.
Assuming your buffer corner is UBL and your Buffer edge is FD, parity will have the UBL and UFL corners switched, and the FD and UB edges switched.
I personally solve it by doing a F-perm that has the bar to the right (imagine a cube with an f-perm on it, and the solved bar is on the right). Then I do M2, then solve by doing U2 M' U2 M' U2 M' U2 M', it's easy, I memorized it.