I released two Pokéball Vivillon duplicates from a glitch because I couldn't find the use of keeping them.
I released like 70+ root and plant seeds because they were from that glitch and needed 1000 posts to level.
I think I released over 200 Pokémon that were just gathering dust and which I had no intention of ever setting as my buddy
Literally all my previously caught seeds. I'm waiting to get the 200 mons medals to release all the other ones I don't want
I'm just about to release my regular Froakie and Kyurem Egg since I now have the shiny forms of them.
I released all my seeds and two regular eggs because I didn't know where the eggs came from when I caught them.
Released my non-shiny Tornadus and a shiny root seed (I couldn't be bothered to level it up. I already have shiny Phantump anyway).
0 because I haven't used the feature yet and I'm still undecided on what to clean out.... probably the duplicate kanto legendary eggs perhaps.
I never released anything yet cause mostly I got things I want to keep, and extra legend eggs I could trade to other players!
I released about 5 or 6 duplicates just to test the feature out. Was legit worried I'd delete my current buddy by accident lol.