First it's setting to shogunate era contradict with event of Gantz origin which is originate from sick young girl German aristocrat who got vision to create mathematical advance to build Gantz.
Another thing it's contradict which is there's no time travel or alternate universe from original series. So who build those tech for them? It's breaking the lore of Gantz itself
What I imagine is they should use low tech technology to fight against those alien (Japanese youkai)
Second, the story itself is rushed. In original Gantz, it takes 15 chapter just to kill onion alien but Gantz E straight to boss fight which destroy character growth for side characters
