During her segment, Donlon revealed that Valorant is currently running on UE version 4.27. As she put it, the team has “squeezed literally every ounce of everything [they] could out of Unreal 4”.
Valorant is transitioning to Unreal Engine 5, but don't hold your breath for an immediate graphical leap with the shift. Instead, this is a "necessary" change that could lead to "new playable ...