"Вас звати Віктор?"
Translation:Is your name Victor?
In the English sentence "You are called..." you is indeed the subject.
In Ukrainian grammar this sentence does't have a subject at all. "Звати" is the infinitive form of "to call". To call whom? - you. "You" is not a subject here but an object in Akkusativ position.
"Вас звати Віктор?" = (literally) "You to call Victor?" = Are you called Victor?
P.S. Come on, same as in Spanish: ¿Cómo te llamas? - it's "te" and not "vos" or "tu" :)
Yes, it is indeed conjugated to "tú", direct translation of the Ukrainian grammar would have been "¿Cómo te llamar?" or "¿Cómo te llaman?" (Як вас звуть?), and well, actually ви = usted or ustedes
What I meant is that it's not ¿Cómo tú [something] ?, it is reflexive in Spanish (te) as well as in Ukrainian (вас, тебе), exactly what you said too, I didn't focus on the verb form :)