Your progression doesn't strictly follow any particular diatonic key. Every note but your G# adhere to Dm or Fmaj scale which sound good over every chord except your G# power chord, but G# is also the b5th of Dm and works as a great passing tone in Dm pentatonic (or natural minor). So just doodle Dm but make sure to anticipate the b5th and emphasis that note in some form of passing up to A or passing back down to the 3rd or root D. You could also use A Phrygian Dominant or D Harmonic Minor, but you're still left with a b5th so you have to anticipate that tone in order to make it work else it will sound sour.

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