I would say 50/50 on this. Both have ways of killing the other and stopping the other from killing them.
In the way of Regulus Killing Gojo, From what I understand of Regulus's Authority, it pauses the movement of space while he can still interact with it to create attacks of pure momentum, If he gets up close to Gojo and just pauses his body DIRECTLY, not interacting with Infinite, not going there, he could just blow him up via a momentum burst.
While Gojo has Hollow Purple and Limitless Void, Hollow Purple doesn't interact with physical objects, it just deletes them, so Regulus's defense is rendered null. As for Limitless Void, it overloads the opponent's mind with sensory input and causes all ability to act or react to anything, so in THEORY, it could deactivate Lions Heart from just Sensory overload. Even if Lions Heart can't be deactivated from sensory overload it could still be deactivated by being disconnected from the rest of the world "It allows them to realize their innate domain by casting a barrier to create a separate space and use cursed energy to construct an environment within it. The target is trapped within the barrier and the domain is completed once it fully embeds the user's innate cursed technique." although this might be a stretch I do believe a Domain in JJK is Cutting off the person from the world, if it is too much of a stretch then ignore this part.