Rewrite URL for only archive page (custom post type)

There is a few Q/A about custom post URL rewrite but I haven’t found any simple answer to what I’m trying to achieve.

My CTP is “event” and I have the current page structure that I want to preserve:

Right now in my theme I use two files single-event.php and page-agenda.php. The latter is the archive page, because I want my archive post slug to be and not so I’ve created an additional page on my backend.

It’s working like that but I’d like to know if there is a more elegant solution to only rewrite my CPT archive page URL while using the proper archive-event.php template?