NAT (IP Pools) and Zone

Hi everyone,

I have the topology below, WAN-1 & WAN-2 are in the same Zone (Internet) with a fail-over scenario between WAN-1 (Primary) and WAN-2 (Backup), what I want to achieve is to create 2 IP Pools as follows to use as a NAT in the outbound policy:
1. IP Pool For WAN1: Mail-Server-WAN1: 195.1.1.10 --> 192.168.100.100
2. IP Pool For WAN2: Mail-Server-WAN1: 88.31.25.10 --> 192.168.100.100

If I create an IPv4 Policy, Source: the mail server 192.168.100.100/32, Destination: 0.0.0.0/0 and put the 2 IP Pools as a Dynamic IP Pool this will work without problem in case of a fail-over will happen.
If not, what is the right approach for such a scenario?

Thank you so much in advance, much appreciated.