i can connect to my pc, pass ebooks in different formats into it and read.

Sounds like you don’t need internet usage. In that case, you can use most ebook readers, including stuff with companies shit on it, and just never connect to the internet. If privacy is the concern, they can’t track you if you never connect to the Internet. You just need to make sure that it has a way to transfer files through usb and can handle epubs.