Sadly this device is only suppored by LineageOS on Nougat.
The official support of /e/ for Nougat will end at Q4 2020, and the official support for athene too.
Hopefully, if there is a working LineageOS 15.1 or 16.0 for athene somewhere, an unofficial /e/OS can be built.
An unofficial build on Oreo is already available (and up to date) for this device :