Well, I find Laravel very flexible. You can use any naming convention you like ( I prefer second one), you just have to route it properly. I don't see what's stopping you to use "sign_up" in url, or whatever you like.

I don't like the flexibility, I think we should have conventions for these kinds of things. I'm currently working in four different Laravel projects with different development teams and we use different variations which becomes a mess in my brain. A Laravel naming guideline would be great, especially when sharing packages with countrollers/routes between projects.

The only problem I have with sign-up is selection. If you double click /sign_up in my example above it selects the whole thing in Chrome. If you double click /sign-up it only selects "sign"

I'm afraid you're fighting windmills... :))