M.U. the Double has isometric view, so I doubt that's the game
There's also another M.U. game that has overhead view, so it can't be that one too (Forgot the name now)
So, it leaves us with the original M.U. and M.U. europe.
They play nearly the same, but M.U. Europe has better gfx.
Oh yeah, and there's also John Barnes, that's IDENTICAL to M.U. Europe, but faster