OSPF advertises remote network because you redistribute pfSense Kernel Routes. right?
if yes try:
option1 : uncheck pfSense Kernel Routes to stop redistributing it.
Correct, when this is unchecked, OSPF does not learn about the route. It will work when pfsense1 is up and its link works because it is the default gateway. Once it loses its connection, it no longer works because the remote site traffic arrives on pfsense2 over the VPN but tries to return via pfsense1 (the default route).
then OSPF in your local network will know about the next hob only which is pfSense 1 or 2 and nothing after them. once the traffic reach one of them it will follow openvpn routes.
This is exactly the issue. Somehow, I need the local network to learn that pfsense2 is now the gateway for the remote site VPN traffic.
still looking how to stop adding route when openvpn is down
This would be great as it would mean everything would work.