I don’t know how edit my post so I will answer to this one.
I tried different techniques but not with [quote=“paulakreuzer, post:90, topic:22327”]
Systemless Xposed
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So you need to do at least step 1a, step 5 and step 6 of level 5 in How to install any app on FP Open OS (for beginners and experts).
After that in microG parameters you need to activate cloud messaging, terminal registering and google safetynet. This is it, you can install Snap and log in without troubles 
You can’t use Xposed with Fake Gapps instead of Tingle (I didn’t test Xposed with Systemless Xposed) and you don’t need to unroot your phone 