Source for both: Protodude from Rockman's Corner on twitter.
Get hyped? Here's hoping that it's not from a cancelled project. Back last year, Capcom asked Japanese fans what new Mega Man game they wanted in a survey included with the original MMLC.
Some extra info from Mellahan:
Before this blows up, a little background:
That artwork appears in Mega Man 8's Museum in Legacy Collection 2. However, it's NOT from Mega Man 8. At all. The art is too new and it was drawn by Yuji Ishihara, character designer on MMBN, MML and MMSF. In addition to the comments mentioned in the OP, this is a digital piece whereas MM8's concept art is all pencil and ink. It's indeed new.
The theory is, whoever put together the museum saw this - the giant hand - mistakenly believed it was Duo, and put it into MM8's museum. Fans believe this comes from an unrelated project currently in production.