Actually, it is possible to chain AirVPN connections so that you enter from one country and exit from another, if you are using Linux. Keep in mind though that doing so will consume 2 airvpn sessions out of the 5 you are allowed instead of just 1.
To do that, here are the steps you need to follow:
1. Set up a systemd-nspawn container that connects to the AirVPN server in Miami
2. Keep in mind the entry ipv4 of the AirVPN server you want to exit from. You can find this in the Endpoint= line in the wireguard conf you download.
3. Set up IP Masquerading in the container from step 1 using iptables -t nat -A POSTROUTING -i host0 -o (name of AirVPN wireguard interface) -j MASQUERADE
4. Remember to also allow ip forwarding on both the contaienr and the host machine
5. On the host machine, run ip rule add to (whatever entry address the miami server has) lookup main and ip route add (whatever the entry address of the airvpn server you want to exit from is) via (whatever the address of the systemd-nspawn container is).
6. Adjust the MTU of the inner VPN(the one where you want to exit from) to 1340
7. Start the inner VPN
8. Run ip rule show. Make sure that whatever ip rule that wiregaurd setup has a lower priority than the rule you entered in step 4.
If you need more help, feel free to ask.