Since the Playstation app got an update and a completely new design when the PS5 was released, I don't know how to change the cover picture for my PS profile from the gallery of my mobile phone. Sony makes their system more complicated with every update. I would appreciate an answer.
Open your profile on PlayStation 4. After the update, it looks a little different.
Next to the item Define online status you will find 3 items.
Click on it to open a context menu.
Now selects Change cover picture.
A folder view opens and you can now select the folder or the game to set a screenshot as the cover image.
Click on the desired screenshot and change your cover picture.
I mean with the app on the smartphone, because you can't take a screenshot on the PS4 on YouTube, for example.