Features used to implement the example

• Set a field as a function of other fields

Example: Set the value of a field of type "User Picker" depending on other field's value

I am looking to be able to assign an issue to a reporter or a user depending on the project name. I am using Jira Workflow Toolbox and it works great if I know the user to assign to. But how can I specify assigning to a role?

For example:

(ProjectA)user1
(ProjectB)user2
(ProjectC)reporter <-- This should assign back to the reporter if the project name is Project C

I didn't understood your question at first instance. Actually, the plugin supports nicely what you are trying to do. You only have to introduce the ID of virtual field Reporter, i.e. %{00006}

Use the following setting rules:

(ProjectA)user1
(ProjectB)user2
(ProjectC)%{00006}

In the last case, the field will be set to the "Reporter"Nevertheless, next version of the plugin will have support to set field of type User (including Assignee, Reporter, etc) or Multi-User with a Project Role. This was what I understood from your question at first instance.