I stumbled upon the Biscuit fork of Crosspoint, which basically make it a tiny covert pentest tool while also keeping ereader functionalities. To be seen if it will keep up with the OG Crosspoint.

https://github.com/yattsu/biscuit

Thanks, do you know if this comment is true still?:

> As of the latest models, XTEINK has started to lock down the firmware to prevent users from installing Crosspoint. So, if you're reading these reviews, beware: the thing that a lot of people bought this for is going away soon.

https://www.amazon.com/gp/customer-reviews/R68BIFNIVY07Z/