The adapter from Jens238 works great. Fiberlogy masterspool refills are smaller (only 700 grams) and less wide, so i made a spacer.
Print it with standard settings: 3 walls and 20% infill.
Stick it to the preferred side of the spool (which doesn't matter, i prefer the lid) with double sided tape.
The author remixed this model.
It's more of an extra spacer, to fit 750g masterspool refills snugly