If the custom fields are a part of a setup you have in Azure DevOps, then the Create Work Item is not going to work as there is currently no way to pass custom fields or attributes within that action item. I think that functionality would be very useful so I suggest raising a feature request with support@freshservice.com. Another way you may be able to do this is with utilizing Microsoft Power Automate or you could also possibly use the Powershell Orchestration application and execute a powershell command to create the work item. Hope that helps!

Thanks Zach, yes I have used Power Automate to fill the values of custom fields. I thought if there are something already in Freshservice that I might have missed to look, so checking.

I will surely raise this feature to support team. 

Thanks again for your guidance.