The intended experience
GameSpot’s report of the director’s comments stresses accessible swordplay rather than designing around repeated, punishing death. That is a stated design direction, not a promise that every player will find it easy.
What about the older Onimusha games?
The series began in 2001, before the modern Soulslike label became common. Evaluate each entry on its own; this answer concerns Way of the Sword and should not be read as a feature checklist for the whole franchise.
Questions, answered
Is it a Sekiro sequel or spin-off?
No. It belongs to Capcom’s Onimusha series. Comparisons between sword-action games do not imply shared continuity or development.