Yes, you can create a custom policy for Azure Logic Apps.
Azure Policy allows you to define your own rules for using Azure, which can enforce security practices, cost management, and organization-specific rules.
Identify your business requirements: Define the expected state of the resource and what you want done with non-compliant resources.
Map each requirement to an Azure resource property: Determine the properties for an Azure resource.
Map the property to an alias: This is used in the policy definition.
Determine which effect to use: Azure Policy supports many effects.
Compose the policy definition: Create the policy definition based on the above steps.
Please note that there are also built-in policy definitions for Azure Logic Apps.
You might want to check these built-in policies to see if they meet your needs before creating a custom policy.