In 2017 he released two free levels that were intended to replace the two levels from Doom 1, episode 1 which Romero didn't make himself.
Then in 2019 he released Sigil, which serves as a 9-map 5th episode to the Ultimate Doom. Sigil is also free if you just want the midi soundtrack version, but there is also a version for sale that includes a special soundtrack by Buckethead.
Last year he announced he was making a Doom II megawad but he hasn't actually demonstrated anything from it yet.
This is unrelated to the upcoming Doom II megawad, made specifically for Ukraine release. So he didn't just snip a level out of an upcoming project and sell it off or anything.