Is there a way to upgrade the Standard version to Gold version without buying it twice?

What other KCD2 products do you find from WarHorse on GoG?

Oh shit, i get it. Thank you. It wasnt very easy to find.

Ask for a refund on your GOG wallet and buy another edition. Gold edition gives you future expansions

Why?
What other KCD2 products do you find from WarHorse on GoG?

What do other products have to do with it? The Gold Edition will automatically give you future DLC (expansions) for KCD2

The regular edition provides only the basic game. All future expansions must be purchased by the player.

So you didn't check. Got it.
Well, you go through the hazel with refund one edition to get the other.
When a quick check would solve everything, with no need to refund anything...
But sure, you do you. I guess.

The game will (!) have add-ons. Like the first game, it had DLCs like ‘A Woman's Lot’ and ‘Band of Bastards’.

If you buy the gold edition of KCD2, you will have future (!) DLCs for free. If you buy the regular edition, you will only have the base game.

Refunds to GOG account are fast.

It makes sense to buy the gold edition to get access to future (!!!) add-ons

For anyone actually looking for the answer instead of ego theatrics.

There is a Expansion Pass DLC that isn't shown in the KCD2 page's DLC block, you have to specifically search for it. It contains the 3 future expansions and Shields of Season Passing DLC, but DOES NOT contain the Galant Huntsman's Kit DLC, so if you want that one, you have to refund the base game and repurchase the Gold Edition.

https://www.gog.com/en/game/kingdom_come_deliverance_ii_expansion_pass

Galant Huntsman's Kit and Shields of Seasons DLC have been added to the store separately now. So a base game owner can upgrade via the Expansion pass and then buy Huntsman's Kit separetely.

https://www.gog.com/en/game/kingdom_come_deliverance_ii_shields_of_seasons_passing
https://www.gog.com/en/game/kingdom_come_deliverance_ii_gallant_huntsmans_kit