Good game to play after Sekiro.Watch
I loved Sekiro but I am not sure what to play now ive'd platinum'd it. I heard fallen order is pretty good but im not sure. Also Dark souls, another fromsoft game, but i've heard its unpolished and clunky in alot of areas.
Branching out from this specific style of game, have a look at Metroidvania and Roguelike games, which are typically 2D but with similar tropes to soulslikes like an emphasis on boss battles and significant consequences for death. They predate soulslike as a gaming trope, but since its popularity has exploded over the last decade, many MV/RL games have started to adopt elements of SLs like punishing difficulty curves and scavenging resources from your last body.