nice to V / Ving

I don't see any, apart from the obvious grammatical one. I'd use more the first at the start of the meeting, and the second at the end (It was nice seeing you), but I'm not a native, so wait for any correction.

Pienne, nicely done.

When you first meet someone, you would side "nice to meet you." At the end of the conversation, you can say "It was nice meeting you" or "It was nice to have met you," or more informally, "nice meeting you." But "nice meeting you" would be odd when first introduced. Likewise, "nice to see you" when you first join your friend for lunch, but "nice seeing you"

Thank you, GG! [F]

"Nice to meet you" normally stands for "It IS nice to meet you", and is
therefore said at the time of meeting (typically while shaking hands, etc.),
while "nice meeting you" is most commonly used to mean "It WAS nice
meeting you", i.e. just before parting, to repeat / reinforce the sentiment
earlier expressed by "nice to meet you".
Alan

Dear friends,

It is a most interesting distinction.

We may say perhaps that «nice to meet you» designates the introductory moment. It is therefore a single event. It is therefore the infinitive. «Nice meeting you» designates however the period of conversation consequent upon the introductory event. It is therefore a process. It is therefore the gerund.

But it

What's the difference in meaning between It was nice meeting/to have met you and It's been nice meeting/to have met you?

https://www.usingenglish.com/forum/threads/242529-It-was-nice-seeing-to-see-you?p=1272651#post1272651

I see no significant difference.