I wasn't able to find a suitable mount for the older Google home mini. Most use the integrated mounting point on the newer Nest mini which isn't compatible.
I have decided to use the contour of it's shape of the speaker itself to pressure fit into place. This does have the benefit of potentially being compatible with the newer Nest mini also but I've not got one to verify if there is enough space for the newer barrel power plug.
I have also decided to offset the speaker from the plug -6mm which allows the speaker part of the mount to sit against the wall for a slimmer overall profile. This does however mean printing with supports is required. So just a word of warning if the face of your plug sockets sit less than 6mm proud of the wall this mount may not be compatible.
With how it's designed it is tricky to get everything into place but I suppose that's the drawback with trying to design it as compact as possible.
Very quick guide on how to make it a little easier:
The author marked this model as their own original creation.