My T has said, in talking about in-person vs. virtual, that when two people are in a room together, there's an "energy" there that isn't there in a virtual session. I would agree with that. He said how he can also get a sort of "aura" from someone, like if they're feeling really depressed, he's better able to sense that in person.

There's also the ability for both therapist and client to see the full body language, not just what shows on camera. I think that can be valuable. For example, I tend to be very fidgety when I'm anxious (well, in general, but more when I'm anxious). If I'm fidgeting with my hands on my lap, he's not going to see that if we're having a Zoom session, but he'd see that in person. Or if I were tapping my foot.

Plus eye contact isn't really the same virtually.