Bingqian Shen Thanks for reaching us here! As you also reached us through GitHub and suggested by author that "We are just rolling out this new functionality and docs will be updated shortly"
Suggestion- networkingConfiguration section has a new property called inboundIpAddressOverride. This can be set to a public IP resource id for ELB ASE and to a fixed IP from the subnet range for ILB ASE.
{"type": "Microsoft.Web/hostingEnvironments","apiVersion": "2022-03-01","name": "[parameters('aseName')]","location": "[resourceGroup().location]","kind": "ASEV3","properties": {"internalLoadBalancingMode": "None","virtualNetwork": {"id": "[parameters('subnetResourceId')]"},"networkingConfiguration":{"inboundIpAddressOverride": "[parameters('publicIpResourceId')]"}}}
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