1st to answer your general Q, multiple listings at the same location often cause ranking impacts. Especially lets say for a Dental office with a practice listing and 3 Dr listings. But when it's different businesses, it poses different issue as well.
Two separate attorneys (sole practitioners) who work out of the same office.
Totally separate businesses just sharing office? Different phones and everything? Plus it could also depend somewhat on if they are using practice or practitioner name on listing.
This one is tricky and depends. Many attys try to game the algo by 'pretending' to share an office with a buddy in another city, just to get a page there. So atty listings are under high scrutiny.
If they both only have that one office and are there full time, then they are allowed a listing. But they may not both rank and there is potential for a merge, but should be OK as long as phone and name are different.
If different suite #s it's best. But don't make one up if there is not one.
A nutritionist who may share office space with other healthcare practitioners, possibly from same field, possibly other disciplines.
Practitioners are allowed their own listing so that's not a problem. But they could all compete with each other and likely only one from a category would have a chance of ranking. Whichever one in that location is most well optimized or most trusted by Google.
Generic Qs like this even with the added detail are super hard because there are still so many variables. So if/when you have a specific case you are dealing with best to post in help section with links so we can take a look. Often when we see the listing we see other issues that could affect our answer.
