Simple equilateral triangle earrings, in stud and fishhook variants. The stud variant, specifically, is made to resemble the earrings that the character Lio Fotia wears in the Studio Trigger movie Promare.
The fishhook versions can just be simply printed on their side, and then have fishhook earring wires threaded through the holes. I used these from Joann's, but anything similar should work: https://www.joann.com/220pk-silver-metal-ball-fish-hook-ear-wires-by-hildie-jo/14149777.html
The stud variant is designed for use with 6mm earring posts. They should be printed in the default orientation, such that the hole for the posts is oriented down. They will need supports to be printed this way, but it allows the earring posts to be inserted mid-print and enclosed. Make sure to include a pause / color change to insert the earring posts just before the cavity is closed. I used these earring posts, but anything with the same dimensions should work: https://www.joann.com/84ct-silver-metal-glue-on-pad-butterfly-earring-posts-by-hildie-jo/14149793.html
The author marked this model as their own original creation.