All of the cases that I downloaded for the Corne Split Wireless (typeractive) didn't quite line up. There was something just a bit off. I also don't like having a female/female standoffs sandwiched between the build. So I designed this one with heat-set inserts and male/female standoffs.

For printing both sides, just mirror the object in your slicer.

Heat-set inserts: M2xH4

Standoffs: M2x5 + 3mm