Wago 2 x 221-412 + 1 x 221-413 angled V clip mount

Edit: In the end, I found the V shape inconvenient, when wiring into it from straight above it was too easy for wire tension to pull the Wago connector loose. I still consider this useful (and cool looking) as a loose hookup wire junction, but I use https://www.printables.com/model/597817-wago-back-to-back-221-412x2-221-413x1-clip for bringing in mains power cables.

Use m3 screws mount up enough Wagos to bring single phase mains power into a project box. The three way connector covers connecting the chassis to ground. There is a mounting hole diagram in the pics.

Also, it's frankly cool looking.

If using this with high voltages or current, you should probably print it in something like https://www.prusa3d.com/product/prusament-petg-v0-natural-1kg/

Multi clip variant.