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Thank you so much, i have a few more in mind:) My main problem with the transparent gifs was that they do not look so good in dark mode, any suggestions?

There is no semi transparency in GIF.

You can see possible examples that i attached below. They don't work on posts but you can observe them with opening images in new tabs.

You can upload PNGs frame by frame on https://ezgif.com/webp-maker and try to make transparent animated images.

or

You can export> render video> quicktime (straight unmatted) in photoshop and convert your mov to webp on https://www.onlineconverter.com/video-to-webp

After these, we need a frontend developer. Because I don't know that can webp format play in posts? or is there a embeded code that plays webp? I hope I could help you.

Or

You must make a really good pixel work on GIF =)

They are also not pixel perfect on light mode too.😊

Ohhhhhhhh looks like a lot of work, lot of technical stuff but i will try some to see:)Thank you much for the advice @bidesign, really valuable:)

You can try to mask them with pen tool on higher resolutions.

Don't make with quick selection =)