That I couldn't find an answer to, unfortunately
There's another game from the same page called "Cavaleiro - Director's Cut" released in 2025 too, may be that one was considered as Cavaleiro II.
Ok now that's neat! Shame it's not a Genesis port!
May be it's their childhood console.
Back then in 2014 the developer has already said they have a dream in the future to create a brand new Cuphead game for the SMS.
And who ever guess that 12 years later it's finally happened.
https://www.smspower.org/forums/14847-CupheadNewSMSGameElansar has reached it's pre-order goal and will move forward with production through Homebrew Factory
Glad to see it's finally happened.