Incorrect display of transparent texture/sprite in editor

Exported some PNGs in my project, set texture mode to Sprite (2D and UI), alpha is transparent, but most of them is displayed with white or black backround.
Screenshot 2024-01-15 132948

Also, when switching from Default mode to Sprite 2D it is not set as single sprite mode, instead it is a blank dropdown.
Screenshot 2024-01-15 135452

Same PNGs works fine in another project. How can I make texture background to be transparent in editor?