While I agree that it was suspicious that the teaser/trailer made no mention of the Retro engine being used, it was still equally suspicious to include the "original footage" disclaimer. The teaser did explicitly state that there would be new features included, which unfortunately still doesn't rule out emulation. Too many red flags for me to lean on the side of emulation however, such as something I've hardly seen mentioned: nearly every platform already has these games emulated either in a bare-bones package like Sega Mega Drive Classics, or in the case of the Switch with the Classics and the retooled 3DS ports. This waiting game to find out this crucial bit of info is bound to drive me bonkers. Super long-shot here, but since this is a package serving to showcase the earliest adventures of Sonic I'd really love to see SegaSonic as like an unlockable or something. Really not banking on that happening for this package, but it'd be a great opportunity to establish exactly where that fits in the timeline. Naturally I assume it is the very beginning.