There are 2 versions, one with only printed parts and one uses regular skateboard bearings.

All Printed Version: You need: 8 Gears 1 Heart 8 Connectors

You can just print the All file.

Print settings: no supports needed. Just print with a standard profile. I used a brim for better bed adhesion.

Assembly: Push the connectors into the heart and then put the gears on top.

Bearing Version: You need: 8 Gears 1 Heart 8 Regular skateboard bearings

Since this version is very tolerance-dependent, I provided many different versions. Start with the 8mm and 22mm version and if that does not fit, go bigger or smaller. Make sure to use the actual filament for the test.

Print settings: Use supports for the gears. The heart does not need supports but maybe a brim.

Assembly: Push the Bearings in the heart and then the gears into the remaining hole of the bearings.