"I need you all."
Translation:Euch brauche ich.
As a native German speaker i would say exactly the same way. " I need you all" or maybe "i need all of you"
The translation here is grammatically correct, but it is no common use in Germany. This sentence would be an andwer to a very specific question, as if you need to make clear which special group is needed. Much more common, and also grammatically correct would be "ich brauche euch".
i think it would be redundant to say that considering "euch" already means you all. it would be like saying "i need you all all"
if "brauche ich" is in the interrogative... then "Euch brauche ich" sounds like 'need I you' Right now I have no need for this sentence! If indeed such a construction of sentence is valid, given it is highly specific or not the simpler example as mentioned below, I shall consign it to the 'backburner' for advanced level German. What is "Duo" doing putting it here when it can only confuse at this learning level? Further translations or likely context of "Euch brauche ich" also welcomed.
if "brauche ich" is in the interrogative
Yes, because brauche is the first word in the sentence.
then "Euch brauche ich" sounds like 'need I you'
Perhaps, if you haven't got used to German word order.
Euch brauche ich. has the word in the second position in the sentence, not the first, so no German would interpret it as a question -- only as a statement.
Don't focus on "inversion" or where the subject is in the sentence.
Throughout the program, Duolingo uses "you all" to elicit the familiar plural form in German. This is in keeping with southern American plural English "you all" or "y'all", elsewhere "you guys" or "you lot", or simply "you". It took me a while to get this, because my native variety of English doesn't use "all" this way. So here, Duo is merely trying for "you all" equivalent to "you" (plural familiar) rather than to "all of you".