UE4 - How to release a game for PS4?

Epic gives you access to its performance with the console branches, so you have to compile your own version. And any project that you already have you can open.
The submission processes to sony are two the first send a gdd.
The second when the game is finished and the release version when you think the game is finished, they test it for a little less than a week to pass the trc and see that everything is correct.

For Epic or Sony it is enough to be a “Solo trader”, you do not need a company. “Solo trader” has the same presence / rights as a company.
But even for Steam it is highly recommended. Yes, steam pays the vat of each country, but the money that comes from steam you have to declare to the tax authority of your country if you don’t want to have problems.