Nope... wont work :-)
I have an M-Tec 68020i 4meg accelerator in an A2000 atm, and I use a Buddha IDE for the cd-rom and harddrive. Works well with kickstart 3.1 installed, probably will even run OS3.9
The A2091 wont work because the memory read/write is on the 'other side' of the cpu socket, effectively hidden from the dma circuitry.
I beleive the Mtec does not map its memory into the zorro 2 space correctly (I could be wrong)
Az