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Yes, src/dst check must be disabled. SNAT automap is the only supported SNAT option (other than none) since SNAT pool cannot technically share the same SNAT pool IPs due to there being two different AZ (subnets don't share space across AZs). A setting of SNAT automap will send traffic out the active unit's self-ip to server side. Upon failover, this self IP will change to the other unit since there is no floating self IP. If you decide to have SNAT none, then return routes from server side need to properly point back to the F5 ENI via route tables. SNAT automap is easier for apps that support it (most).
Also, check this...
https://devcentral.f5.com/s/articles/deploy-bigip-in-aws-with-ha-across-azs-without-using-eips-33378