this has been discussed many times, and it varies from people to people.
i can attest that when i started smoking weed, i'd get full blown hallucinations, OEVs, CEVs, auditory hallucinations, i couldn't even function or understand what i was happening where i was or anything. i would compare it to a mild ~2-3g shroom trip, though less introspection and 'feelings of enlightenment' and more of total confusion and non-sense visuals. note that at that time i had never done psychedelics before.
that being said with time i started smoking weed frequently and that quickly stopped. to this day if i smoke a lot of weed i do have OEVs and mild CEVs, but honestly i doubt it'll ever be like my first times where a few hits would send me out of the solar system.
but i personally am very sensitive to weed in all ways. i can't smoke it frequently at all or i start losing the grip on my sanity, and when i do smoke, i smoke just enough to feel giggly and stupid and stop, otherwise i know shit gets unpleasant
weed is a very idiosynchratic drug imo. some people can swear they never hallucinated from it. i guess it shows that may be our endocannabinoid systems can vary a lot? also i'd love to know the mechanism behind weeds psychedelia and all that jazz