Here's hoping they don't try to go all cinematic and keep it mostly environmental though in the story telling department.
If they go cinematic, that'll be a departure from every game they've done before. From what I can recall all of their games have been teased by a CGI trailer, then having the opening as CGI followed by cinematics being "uh oh, boss time".
Based on the description above it sounds like Dark Souls in a new setting. Perhaps, as you say, marrying the skill trees\rpg elements from Sekiro along with the weapon\armor variety of a Souls game. Which would be fantastic. That's my favorite thing about a Souls game. Exploring the world for the first time, looking in every nook and cranny for weapons, armors, spells.
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