It's not possible to change the actual URL (slug) of the Collection we create. That's very clear. However, what we can change is the name of the Collection which is visible inside the Webflow editor. However, when I do that, what happens is that the actual Tempalet page that is created (visible in the pages overview), will stay the intitial name I used before editing the name.
So for example, I created this collection:
Collection Name: Team Members
Then I realized it shouldn't be Team Members, but Team Groups. So I changed it;
Collection Name: Team Groups
Slug: team (stays the same)
Now in the the page overview it still says "Team Members". Which causes confusion. As far as I'm aware the page title in the pages overview is not linked to the slug (similar to how we can change page titles), so please update these titles according to how they are written down in Collections.
Hope that's clear. It will help me if this can be done!