For a matching pair just mirror the parts in your slicer.

I recommend rotating the "main support" so that it's essentially upside down with the dovetail slot sticking up in the air. (see picture)

For the "inlay" you'll want to print it on it’s side so the hexagons lie on the bed.

Go for min. 3 wall lines, and an infill of 20% or more.

Please feel free to post pictures of your colorscheme :)

Tolerances are 0,2 mm on all sides for the inlay, I printed it on a raft in order to avoid any surprises when inserting into main support. (elephant foot)

Check out my newest design of a hand-cranked, spring loaded catapult :D https://www.thingiverse.com/thing:5746831