Can you please post a layout plan of the proposed remodel? Are you making a diagonal work corner--including countertop? If not, triangular spaces make for odd spaces so will you be closing the countertops with cabinetry at ninety degrees with access into the corner spaces?

It is important that you follow the LG's required space for the surrounds of the units. You might also allow for future widths should you change brands or said brand has a changed units and surround dimensions. There is no reason that a diagonal setup will not work unless you have a requirement of a 180 degree door swing on the units.