In its different modules (especially those for workflows), the JSU app JSU supports many different field types . System fields, as well as such as system fields and custom fields. However you should be aware, that not all field types are supported. Also , and not in all combinations. We think we aim to cover the most important field types and still are continuously adding and improving which and how different field types are supported. But the one you need, might just not (yet) work. Some custom fields of other third party app -party apps might never get be supported.
For that reason, you should always test anything you do with the JSU app with fields. Before you buy a license for JSU, You can try it with a free 30-day evaluation license, if it works for you.