Hi srshue
While SoapUI Open Source doesn't natively support GraphQL like Postman does, you can still work with GraphQL using manual workarounds.
To do so, manually create your queries and mutations in the request editor.
For queries and mutations requiring variables, specify them in the Query Variables panel. Additionally, leverage Groovy scripts to automate tasks such as dynamically generating query parts or handling responses.
Although SoapUI lacks a built-in GraphQL schema loader, these steps enable effective GraphQL testing and exploration.
To learn more - please refer this help article - Docs | SoapUI
Hope this helps - Happy to help further!!
Thank you very much and have a great one!
Warm regards