Joe Manganiello -- Dumps Ballin' Bachelor Pad ... Moving in With Sofia?

Sofia Vergara's fiance, Joe Manganiello, may be ready to have his chick, her infamous eggs and himself all under one roof ... because he's unloading his awesome Sunset Strip pad.

Our real estate sources say Joe moved out to sell his swank 2,500 sq. ft. 4bed/3bath digs. Asking price ... a cool $2 mil, but the big question is whether he's bailing on his oasis -- hot tub and pool included -- to say hola to a place with his woman.

He snagged it for $1.8 MIL back in 2013 ... so it's not like he's gonna make a ton o' cash off the sale. Plus, no one would be shocked if he was in a rush to get in more Sofia time.

But she better have a hot tub.