How to stop Photoshop 25.9 from addiing "-edit" when using "Save"

This is controlled in Lightroom Classic, in Preferences / External Editing, at the bottom. You can set the kind of renaming you want using the Filename Template Editor. If you want Photoshop to save an image with the same filename it had in Lightroom Classic, the filename template you assign in External Editing preferences should use only the Filename token.

The reason they append a suffix by default is to avoid the situation where someone edits a copy with the exact same name as the original, and ends up overwriting and losing the original. But if you know what you’re doing, you can control the file naming as shown above.

Because of that reasoning, the suffix is added only when you’re having Lightroom Classic send a copy of the original to Photoshop. If you have Edit In send an original non-raw file, then because you’re intentionally editing the original then the filename won’t be changed in Photoshop.