Cannot Add TestLeft MSTest Unit Test in MSTest Test Project Core in .NET 6.0 in Visual Studio 2022

Hi,

.Net 6. is supported by TestLeft since version 15.31 (https://support.smartbear.com/testleft/docs/general-info/version-history/15-31.html)

Assuming that you've followed procedure described in https://support.smartbear.com/testleft/docs/tutorial/vs/create-project.html, I don't have any good guess at the moment and would suggest to create Support ticket via the https://support.smartbear.com/aqtime/message/ form.