A Labeler with a BG what kits all letters together and an option to make it "over 3d-ish" (and some more settings). One or two lines.

The .stl is just an example. You should have OpenSCAD (open source, small, great) and customize your own labels! The fonts are given by your OS. (If you need help in OpenSCAD, watch in 'Help' in main menu, in this case 'Font List')

Print instructions

on BG to Letter change (in the example at 0.4mm) use 'filament change' in slicer or 'M600' directly in gcode to make the right contrast