Thanks for reaching out about this in the Community!
Currently the way the app is set us it's not possible to play your local files on the PS4.
If you think other users might also like it, go ahead and create an idea on the relevant idea board. We always take new ideas and feedback into consideration to improve the app. Here you can read more on how ideas work.
We also suggest checking this help article for useful tips on how to submit an idea. As a heads-up, it's good to know that the higher the number of votes an idea gets, the more likely it is for the idea to be implemented.
Hope this helps. Let us know if you have any more questions.
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