Kimmich, Gündogan and Goretzka is the save variant I believe. Fitting in Kroos is more demanding from a tactical perspective but also has higher potential, IMO. Busquets, Xavi and Iniesta didn't need a work horse besides them either and Kimmich, Gündogan and Kroos is probably closer to them than any midfield any nation fielded since Xavi retired. In a way, playing Goretzka would be a confession that you can't get a midfield to work that is better on paper.
I mean, it's Löw in the end but imagine Sané and Gnabry on the wings, Havertz as a false 9, Kroos and Gündogan on the 8 and Kimmich as a 6
Another idea would be to start Goretzka in midfield and Kimmich as an RB but allow him to drift into the center Cancelo/Lahm/Alaba/Zinchenko under Guardiola style. Goretzka could then focus on his runs into the box.