Uploading encrypted backup to the cloud, best solution?

Hello everyone, I have the following "problem":

My current backup strategy is to use Ashampoo Backup Pro 17 to upload my most important files to the cloud in encrypted form.

The "problem" with this, however, is that I back up the files to an external hard drive, into the Dropbox folder, and then upload the files from there, because backing them up directly to Dropbox took far too long. And the next problem is: I'm "afraid" that no one will be able to access the files if something happens to me, because, to put it from the perspective of a non-technical person:

He has to go to the PC, open the program there, search for the backup, open it using the PW Manager, for which he first has to get the PW Manager open and then, if he fiddles around a bit with the folder structure, he can access the files in Dropbox (since the path is a bit inconvenient due to external storage).

And regardless, it's not easy to access it from another device because of the stupid folder structure the backup software uses.

So, what could be the solution to the problem?

-Upload directly unencrypted. But then we're back to the topic of "There's a reason to encrypt stuff."

-Create a 7-Zip archive, encrypt it, and then upload it. Advantage: No intermediate software required. Disadvantage: This would be a backup that is difficult to keep up-to-date, as you'd have to repack and unpack it (but you can commit to doing this once a month). (And I don't know if you can upload an archive as such without it becoming corrupted and thus unopenable. I'm not technically savvy enough to know that.)

-Cryptomater or Veracrypt. But I've also come across enough comments talking about corrupted containers that couldn't be opened and were thus gone forever, and that would be stupid, too.

Conclusion: I'm probably too paranoid, but how are you approaching this/what would you advise me to do? I can't really find anyone who can help me, so I thought I'd try here. Thanks to everyone who took the time to respond or read this.