Hello @gmorgan28
The approach outlined below is the one I used to export the Planner Tasks with their Checklist items.
- I use the same trigger you have, so nothing different here.
- For the next action, I added an Initialize variable action. Set the Name property to the name of the variable, and the Type to Array.

- For the next action, I added a Planner - List tasks, same as the action shown in your screenshot.
- For the next action, I added a Filter array, same as the action shown in your screenshot and the same filter.

- For the next action, I added an Apply to each and renamed it to ForEach Task. This action will loop through each task and execute several actions within it. For this one, I set the Select an output from previous steps to the Body of the Filter array action above. Then inside this loop I added the following actions:
- The first action added to the loop is a Planner - Get task details. As the name implies, it is being used to get all the details of each task.
- The next action added to the loop is an Apply to each and renamed it to ForEach CheckListItem. This action is being used because the Checklist property is an array and the flow needs to loop through each item.
- Then, inside this loop, I added an Append to array variable action so it can capture all the columns that will be used in the CSV export. The first 5 properties in the screenshot below come from the output of the Filter array action, and the remaining ones come from the Checklist property in the loop.
Note: the lastModifiedByuserdisplayName property is set by using an expression. For some reason, this property is not available in the Dynamic Content window.

- After all the looping is completed, the next action I added is a Create CSV table. I set the From field to the array in step 2 above and I left the Columns value to Automatic.

- For the last action, I added a SharePoint - Create file to store the CSV file being created with all the information from the Planner Tasks.

Please try this approach and see if it works for you. Also, please reach out if you have any questions.
Regards,
Fausto Capellan, Jr
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