"θα είσαστε εδώ;" Γιατί είναι αυτή η απάντηση λανθασμένη;
Thank you it has been added.
Εσύ, θα είσαι εδώ; Alternative?
Of course it should have been here. I've included it many thanks.
Is "Θα σου είσαι εδώ;" also acceptable?
No, that's wrong I'm afraid. You can say Θα είσαι εδώ εσύ; / Εσύ, θα είσαι εδώ; / Θα είσαι εσύ εδώ;
You cannot use σου as the subject of the verb because it's not the nominative case, it's the genitive.
Oh yes, of course, I should have thought of that. Thanks for the explanation.