A "best pattern" is tricky. An OK pattern is easy. Whenever it's a hub that has to carry torque, you want a (somewhat)tangential(crossed) spoke pattern.
High flange hub, 4X is out. Even 3X might be tricky. So you're looking at 2X or even 1X. I've done mismatched builds, and they can be a right pain.
36 from 40, I'd probably try for an 1X and simply chance to use spoke lengths for a regular 36/36 build. Might need 4-8 spokes of a different length.
Or I'd make myself some adapter rings.
3 mm aluminium sheet metal, inner edge overlaps the hub flanges and attach through the spoke holes. Outer edge protrudes enough to allow for new spoke holes to be drilled with the correct spacing and hole count to match the rims.
There MIGHT be a 40-to-whatever combo that'll work out symmetrically, but I've haven't found any easy way to determine that.