There is a kernel source code released by Meizu so i think it’s possible to build a linux distribution that works on this smartphone.
As i know, you cant unlock bootloader on Meizu phones, so you cant install custom roms.
There are people who have successfully installed TWRP and unlocked the bootloader on the 4pda.ru forum.
I wonder how they did it.
I can’t even downgrade flymeOS.
So after searching the web i can confirm that your phone have twrp support https://twrp.me/meizu/m1721.html so you can try install some custom roms on on it, but /e/ is based on LineageOS and there is no it official support for any meizu device, so i can’t even build unofficiall /e/ rom for you, but you cant try your luck with other custom roms which are availiable for your device.