Courtesy of a user on ResetEra and twitter named lyte edge found a VERY interesting bit of info. Apparently the western release of Dynasty Warriors Xtreme Legends Definitive Edition on Switch (which just came out today on the eShop), actually recognizes and is compatible with the save files of the Japan-only Musou Switch ports released last year in their proper English names.
The games of which are Warriors Orochi 3 Ultimate (pictured), Dynasty Warriors 8 Empires, and Samurai Warriors: Spirit of Sanada. Each game’s save file gives players of DW8XLDE some bonus goodies when booting up the game. Warriors Orochi 3 Ultimate gives you 500 weapons materials, while Warriors Orochi 4 (the only officially confirmed compatible game in the west) gives you 100,000 gold.
It makes sense for the trio to get localized since all three already were localized on other platforms such as PS4. So it’s only a matter of Koei Tecmo just reusing said localizations and releasing them on the eShop.
HUGE thanks again to lyte edge for the awesome find!