I posted this last week
https://community.esri.com/t5/arcgis-pro-sdk-questions/standa-alone-exe-cannot-run-corehost-sample-q...
Over the weekend I wondered if it's even possible to do a spatial query overlay in a stand-alone "core host" app. This would be like doing a select by attributes in layer A, then a select by location for features in layer B and then loop through the results to read attribute values. It seems like a lot of Pro functionality requires you to build an add-in. This is obviously a must for tasks that require interaction with a map or the UI, but what about projects like mine that just need to do a spatial query? We could do this via ArcObjects with ArcMap, but we need to migrate our project to Pro. I understand that I'll need to check for Pro licenses (that part of my code already does). I want to avoid add-ins because every time you want to debug an add-in, you have to restart Pro, then load the project and then do all of the clicks to get your add-in to run. That's time consuming and it gets a bit frustrating.