Given the data sheet / package foot print it isn't a big deal to modify a footprint and make a new part, but as Old_Grey said we would need a data sheet. Google finds references of a sort to qfn 3.5mm but it seems to be stencils and implies a .4mm pitch (but all the package outlines I can see are .5mm pitch) so the chip and package datasheet that you need are the first step.
Peter