I printed Mlotz' design https://www.thingiverse.com/thing:5499650 and loved the simplicity and effectiveness of it.

I created this remix by adding 2 opposing screw holes at 60 mm. This way you can attach the mount directly to standardized (EU) flush wiring boxes. (brands like ABB HAF and Attema, see picture)

Works with (at least) TP-Link Omada EAP225 and EAP 245 v3 and v4. Use 3 or 4 mm screws