Yeah, I wrote about it months ago. And talked with a Graphene developer, why they supports the Pixel phone only. He replied that something privacy related things that Graphene use feasible in Pixels only.

I use LineageOS with MicroG, a completely degoogled phone.

BTW: if you haven't google email address u can't use the GooglePlay.

And F-Droid is not enough unfortunately. So you have to use alternative stores, like Apkmirror, Apkpure. I don't prefer Aptoide because this little dick wants to get supervisor rights on mobile.

And last but not least: to check the appropriate apk downloaded from an alternative store you should use e.g. Tracker Control (TC) it is available on F-droid, PCAPdroid, also from F-droid. And a reliable firewall, e.g. Netguard or if you have rooted phone the best is the AFWall+

Sorry for this long reply...