4Gamer.net has an interview with Hidetaka Miyazaki where the From Software president reveals the Dark Souls developer is working on two different unannounced games. At least we trust that he does, as this is all in Japanese so we're relying on the translation on Siliconera. He says both games are "From Software-esque," so in their own words, prepare to die. Here's word:

4Gamer: Please tell us about development beyond Sekiro. In a previous interview in June 2016, you said that the development lines went from 2.5 to 3.5.

Hidetaka Miyazaki, President: “That’s right, so if we go back to talk about the lines, at the time we had 3.5 development lines that were moving. 0.5 of that was Déraciné, and 1.0 was Sekiro. The remaining 2.0 are the unannounced titles. As for Dark Souls Remastered or Metal Wolf Chaos XD, those were requested by outside companies, so they are not included as part of the 3.5 lines.”

So does that mean you have two unannounced titles that is currently being developed?

Hidetaka Miyazaki: Yes. I can’t share any further details at this time, but I believe they are games that are very From Software-esque. I think it’ll still be a little while longer, but we’ll let everyone know once things start to take shape.”