Daniel Juncadella and Maximilian Gotz have both been promoted to the crack HWA squad as part of a major reshuffle of Mercedes's DTM driver line-up.
The pair both drove for Mucke Motorsport in 2015, but this season will slot into the lead Mercedes squad alongside Paul di Resta and Robert Wickens.
"I have mixed emotions about the move," said Gotz.
"I have always felt very much at home with Mucke, but obviously it's an honour to be driving now for the most successful DTM team of all time.
"Although there are no great differences between the Mercedes-AMG DTM teams, HWA have something of a legendary status in the DTM. All previous Mercedes champions have come from this team.
"But for me, it is also clear that I now have to further raise my performance so as to score points on a regular basis and to finish on the podium some time soon."
The shift means Mucke will have an all-new line-up for the upcoming season, with Christian Vietoris shifting across from HWA, and Lucas Auer coming from ART Grand Prix.
The Austrian already has a history with the Berlin-based team, having raced for them in Formula 3.
Gary Paffett will stay put at ART for 2016, and will be joined by newcomer Esteban Ocon, who won last year's GP3 title with the French team.