We had to use Perforce (Helix Core Cloud) at my last game studio, and it is the de facto industry standard that most of your creative staff is already familiar with. The programmers don't love it, but they don't rule the roost in games. It's also the safe, verified default for working with Unreal Engine 5.

It does show its years though. We were one of the first users of the Perforce cloud offering, as we were small and didn't want to self-host ourselves, but it was a bit of a rickety experience. You had to register an Azure account in order to be able to access the service, and you had to ask support to modify things like triggers. Coming from the world of GitHub and other SaaS products, you could tell it was an attempt to retrofit an older model into a new skin.

The Git LFS path has some unofficial support as well, but you are on your own when things go poorly. Epic doesn't provide much help there.

Competition in this space is welcome, especially if they're planning to make it fully officially supported by the Engine.

I wrote about why merging files isn't as common in the world of game dev for folks coming from the world of text: https://www.kuril.in/blog/why-game-devs-dont-merge-files/