Keep a logo's "fade-out" always 5 sec. from video's end

Currently I need to render approx. 100 videos in Premiere Pro and I am looking for the most efficient way to do it.

Each of those 100 videos is very simple: just one main video file (which is always different and always has a different duration) and a logo (which is always the same) which should fade-in exactly 5 seconds after the video starts and then fade-out again exactly 5 seconds before the video's end.

To save time I tried to create a "template" project, which already contains the logo and the fade-in and fade-out, so I would just 100 x replace the main video file and then render. But because each main video file has a different duration I have to manually reposition the logo's fade-out to exactly 5 seconds before the video's end after I replaced the main video file.

So I was wondering: there has to be a smart way to keep the logo's "fade-out" exactly 5 seconds from the end of the main video file, no matter how long that video is?

Any help is highly appreciated, thanks!!

Kind regards,

Nick