Selling Overlays online

[frozen ermine]

I made a very good overlay pack do any of you know a good place for me to sell it?

[inland drift]

You can try
Adobe Stock (any stock platform really)
Behance
Envato
Creative Market

Consider if your overlays can be used for other things than photos (Streaming platforms for example) and you could add
Video Hive
Gumroad
Artstation
Elgato

There are probably thousand of others