Apologies in delayed response.
For AKS, this is created by the platform. Same frontend IP cannot have both properties. i.e Inbound rule - SNAT and outbound rule.
If you are using an IP for outbound rule and if the same IP is part of Inbound rule, to avoid the error mentioned, you need to enable this property ( -DisableOutboundSNAT ) in the Inbound rule.
Try to modify the rule for disabling the outbound SNAT, you can refer this document. Then you can create a outbound rule like below:
ex:
$rule = New-AzLoadBalancerRuleConfig -Name $lbr -Protocol $pro -Probe $probe -FrontendPort $port -BackendPort $port -FrontendIpConfiguration $feip -BackendAddressPool $bePool -DisableOutboundSNAT
Also, please refer this document for creating outbound rule config.
Hope this information helps.
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