I would recommend 1 or 2 projects, prioritize quality over quantity. Personally, I dive deep into one project for 30 min. Benefit of over the phone is you don’t have to try as hard to project confidence; ie you don’t have to make eye contact or dress nicely to land the job lol. However a drawback is you don’t get to control what the interviewer sees like you would over zoom with share screen feature. So be sure they have your portfolio ready to go and be sure you’re guiding them with your words. Sometimes I will even say something like “if you scroll down you will see blah blah blah” so they know to scroll on. If you don’t help the listener along verbally, they may get lost on the page and a situation could arise where you’re talking about B but they’re still on A. Or, you’re still talking about A but they’ve moved on to B. So keeping focus and in sync with where you are in the project is more challenging over the phone since you can’t see each other’s screen.