is there somewhere similar to panthip plaza in chiang mai?

Yes there is a Pantip in Chiang Mai

Just use google all the info is there

However, Chiang Mai Pantip is not too big on illegal software. There are some shops, but it's not the zoo that is Pantip Bangkok. It's rather nice really! But for copied software, I think you can do better for example at CM Centre at the intersection of Chotana Road and the superhighway. (Khuang Singh Intersection). Or at the old computer malls on Maneenopparat road, like Computer Plaza.

Cheers,

Chanchao