Palworld had trailers featuring gameplay in 2021. Besides that, there are lots of games where you throw an object to add a character to your party. Including another earlier game by PocketPair called Craftopia. World of Warcraft added “battle pets” where you can throw a cage to catch animals and add them to your battle pets roster to fight against other trainers in 2012.
to add on to this, the video is dated in june 2021, and the patent show in japan wasnt registered until december 2021, which means palworld was already well on the way prior to them actually submitting these patents.
all three of the patents listed in the article have a japanese patent registered on 12/22/21. Palworld appears to have working gameplay mechanics by june of 2021 as shown by their announcement trailer.