First of all, I have read all the content and what needs to be done on this subject in the forum one by one. I created and sent the images according to what was written, but they were rejected. I just read a few titles again and realized this. Many users suggest uploading images in different sizes and different shapes, and I am thoroughly confused. For this, it will be much more useful if a developer whose content is published in the Play Store shares the images he has used, with the dimensions and contents specified. Because the Play Store process is really tiring. Or please, can anyone help me with this issue via e-mail? Thanks.
Email: [edited out]
Featured Image : 1024x500 jpg
Watch Face Icon : 512x512 png (transparent)
Phone : 960x540 and 540x960 jpg
Tablet :960x540 and 540x960 jpg
Wear Os : 450x450 jpg background black
Ozan thank you.
I would also like to ask this. Is there a limitation on the watch brand/model (as mockup) used in the image content?
(Çok teşekkürler Ozan dostum-) 
It depends on which watch brand you use. If you add a Rolex mockup, they won’t accept it. 
and You can upload up to 8 images.
Thanks for the answer. I think I will encounter a different step when I get past the approval process for the images, but even this will be a great success 