This ends up a win-win to avoid fees, but you have to verify identity and tickets

1) Best is to meet in person for the swap, but transfer the tickets electronically
2) do a video call where they can show you the tickets or screens are
3) have them message you on a second verifiable social account. Note there are a lot of stolen or fake FB pages, so scroll through their history: when was it started, how often is it used, who are the people engaging in the account
4) have them send picture of a mail piece with name and address
5) calling helps, but is not enough. You need to have a second way to verify identity

You can get creative, but usually they’ll agree to it if the tickets are real because they are at equal risk of being scammed