Assuming you want to
1 – capture the requests to be able to categorize them (like by looking to its HttpRequest/
2 - do a specific follow-up action REST call to the desired API (with a specific proxy config) based on the (
Mind you that there is a Native proxy configuration available on the Call REST activity, which you can use also by configuring in a dynamic fashion (if $EnvironmentDev then $ProxySettingsDev else if $EnvironmentPro then $ProxySettingsPro..)