Only thing I can think of right now... Of course you have to register, but I'm pretty sure you already are registered there.
- https://www.kobo.com/us/en/p/free-ebooks
- Pick a category/genre
- Sort by date - newest
Otherwise there is
https://www.ereaderiq.com/freebies/ but it's for Kindle books so... You'd have to find something you want and then search for it at Kobo, Google Play or another site to see if there is a free ePub version available.
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