It was inevitable that Tengen was going to be available in Demon Slayer -Kimetsu no Yaiba- The Hinokami Chronicles. You can buy the character pass to get Tengen and other characters for $24.99 USD. There is also a free update that contains a new stage, the Entertainment District.
I hope that we get the rest of the Hashira as well as the new demon's that we see along the way.