Guys Good News,
i install today Rasbian OS Jessie for my Raspberry pi 3 model B and what happends hoooola nothing. haha
No Error nothing fail.
MagicMirror install all without a Error, OS Stretch sucks for the MagicMirro so Guys never Use that. Use OS Jessie for The MagicMirror. PEACE!!
It works now YUHUUUUU.
Thank you all for helping me 
now i build the Frame and install a few Modules.
Thank YOU ALL!!