On the topic of peace and peace talks, that Zelensky also mentioned in Argentina, this is the first issue that comes to my mind: territory.
Ukraine ceding occupied territory to Russia – why would they do this? It would be a reward for Russia for conducting an illegal invasion. It would be a terrible precedent, showing the world that it’s a doable and acceptable procedure, where you get to keep stuff at the end.
Russia returning occupied territory to Ukraine – why would they do this? It’s what they came for and so far they can militarily hold onto it. Making them stop the occupation needs an incentive. But what could that be? From who? Financial? Political? In what magnitude? Wouldn’t giving Russia anything then again also be a reward? They invaded, occupied for a while and then get some goodies for leaving?
I really don’t know how the plans in the drawers all over the world look, from people that are in decision making positions. And we haven’t even started about reparations for war damages yet.