Is the correct versiin really "Dlaczego wszystko null trudny?", as the mobile app tries to convince me?
Doesn't seem to make sense. "Wszystko" is grammatically neuter. What do you mean by "null"?
That's what it wrote. I suspect it missed "jest" but it did not write "jest", it wrote "null".
Seems like some mobile app error...
Please can you explain the word order as I don't understand it in this sentence.
It's the same as in an English affirmative sentence, since Polish doesn't use subject-verb inversion for questions.