/ip firewall filter add chain=forward dst-address=2.2.2.2 action=accept
/ip firewall nat add chain=srcnat dst-address=2.2.2.2 action=masquerade
/ip firewall nat add chain=dstnat dst-address=1.1.1.1 protocol=udp dst-port=3000 action=dst-nat to-addresses=2.2.2.2 to-ports=3000