This is not a regression tested in //UE5/Release-5.0 CL20979098
After migrating an asset from an older engine version or upgrading a project to newer version Blueprints carried over can not be casted until they have been opened or placed in the view port.
Cast To BP_Test node shows up.
BP_Test isn't visible until the BP_Test is compiled.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-173449 in the post.