Wexter

iptables -t nat -A POSTROUTING -d RPI_VPN_IP -p tcp -m tcp --dport 554 -j SNAT --to-source VPS_VPN_IP

iptables -t nat -A POSTROUTING -d REG_LOCAL_IP -p tcp -m tcp --dport 554 -j SNAT --to-source RPI_LOCAL_IP

/ip route add dst-address=0.0.0.0/0 gateway=1.1.1.1 routing-mark=ISP1
/ip route add dst-address=0.0.0.0/0 gateway=2.2.2.2 routing-mark=ISP2
/ip route add dst-address=0.0.0.0/0 gateway=3.3.3.3 routing-mark=VPN

/ip firewall mangle add chain=prerouting src-address=192.168.0.2 action=mark-routing new-routing-mark=ISP1
/ip firewall mangle add chain=prerouting src-address=192.168.0.3 action=mark-routing new-routing-mark=ISP2

/ip firewall nat add chain=src-nat action=src-nat routing-mark=ISP1 to-addresses=1.1.1.2
/ip firewall nat add chain=src-nat action=masquerade routing-mark=ISP2