Information on the store page is sparse on which of the PC ports this is. Is this the best port (SourceNext, Japan only [until now?]) or not?

Nope, is the Original European version, main reason I bought the bundle was i believed it was the SourceNext Ports but alas, had to refund them

They can be converted to SourceNext/mediaKite ports with patches. They will then work with Classic REbirth

So, will GOG/Capcom provide that? Or do I have to hunt those down to get the SourceNext (the definitive ports) myself?

- install the japanese game
- install patch from https://classicrebirth.com/index.php/download/biohazard-pc-cd-rom-patch-version-1-01
- install rebirth mod from https://classicrebirth.com/index.php/download/resident-evil-dll-fix-for-classic-edition

That should be it.

This is nice and all. But it's just a shame really that you have to still use mods to get the best possible experience with this game. Instead of actually having the best way to play it out of the box. An official legal release should make sure to give the experience. But who am I kidding. Thats the industry, almost never doing things right. But there will be further patches I hope.

I waited years for getting the Classic Resident Evil PC ports being re-released here and you can guess what would had happened, if they had used MODS with these releases, people would had complained and that GOG used their creations without their permission bla bla bla.

I mean should GOG release a patched version of Fallout New Vegas that comes with mods? Maybe? But the same thing would had happened there as well.

I wish someone could make a Resident Evil GOG patch, that makes it easier for newcomers that don't know how to install mods and i already patched my game and i have now the best way to play the original Resident Eil.

But when it comes to RE2, by preferred version of the game is on N64

...Except, these aren't the Japanese game/SourceNext, right? So that means I have to go hunt down the Japanese version/SourceNext already to "convert" these if I buy them.

This goes into: Why would Capcom release this when everyone knows the defintive version is SourceNext? They could've easily contracted that.

I also wondered this, but I discovered that the GOG version of the game does have the Japanese game files that can be used to apply the mediakite patch and REbirth mod. This video I think does a good job of showing how to install the patch and mod on the GOG version of the game: https://www.youtube.com/watch?v=luPmHLio1AM