It looks like you are using the Zephyr Scale app (former TM4J app) for test management. eazyBI has integration with this app, and you can import testing data (test plans, test cases, tests cycles, and execution results) in eazyBI.
First, you might want to import data from Zephyr Scale (former TM4J) in eazyBI. More details on how to do this and what new metrics and dimensions will be available: Zephyr Scale Test Management for Jira - eazyBI for Jira.
Issues covered by test cases are represented in dimension “TM4J Requirement”, and the assigned test count is represented in measure “TM4J Test Cases created”. To make this dimension and measure work for your report, you might want to create a new calculated measure in the Measures section.
The calculation would get the Issue key on report rows, look up this issue in the “TM4J Requirement” dimension, and then check how many Test cases are associated. The expression might look like this:
--Zpehyr Scale specific measure showing test case count
([Measures].[TM4J Test Cases created],
--look up issue from report rows in TM4J requirement dimension
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