Not an expert here but I never convert the vfr videos (my phone also records vfr only) and haven’t had an issue so far. I assume not converting would affect something like the exact frame you cut/trim a video or apply an effect but I don’t personally care if there’s a 1-2 frame offset in the final export (and by offset I mean different to what you see in preview).
If you can export the video succesfully and play it after with no major issues I think you’re safe.