Hi.
What do you mean by the term “de-googled”?
Just the fact, that there are no Google rlated apps or deamons running?
As a LineageOs user myself, I’m pretty sure there are no Google-ish things on my phone, but with the asked question, I think that I just try out one or all of the suggestions by @SameExpert just to be (more) sure.
The fact, that no single apk which depends on any Google service I tried on my (other experimental) S5 did run (sometimes not even install) makes me very confident, that at least with LineageOS you’re pretty “safe”.
But as we IT-Tinfoilhats use to say… “You never really know…” 