The adapter from EMAX on Thingiverse broke easily and was based on a pre-production version that didn't have a capacitor on the back of the drone, causing it to dent the capacitor on mine.
This is a little beefier and slides over the standoffs, making it easier to remove the top plate.
I added a rotated version in which the adapter is parallel to the build plate, I printed it like that with supports that snap off easily.
It hasn't been crash tested extensively, I'll update the thing as soon as I get some data. You can change the "Connection thickness" or "Connection height" variables in the customizer to make it a little beefier.
For other drones you can try playing around with the standoff seperation/height/radius parameters to get a model suitable for your quad.
I printed the rotated version with "Sheath around the support" disabled to make supports easier to remove.