Repro Rate: 10/10
This issue occurred in the live build of //UE5/Release-5.1 at CL 23058290.
This was regression tested against //UE5/Release-5.0 at CL 20979098 and is confirmed to not be a regression since the issue also occurs in this build.
Actual Result: Error, failure to create plugin.
Expected Result: Attempting to create a plugin with the minus character in its name should result in either an error warning about using an invalid filename or allow the user to successfully create the plugin.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-172994 in the post.