I have a question.
Can I configure a different Share URL?
For example the Nextcloud is installed on cloud1.cloud and if you share something it will be shared over the domain cloud2.cloud.
Is it possible to change the share URL?
Unfortunately you’ve not provided any information about your environment to better understand what you’re looking for. An “Share Renamer” app exists to rename a share, but if you want to have a shared file listed outside a users root view, you can set a general parameter in the Nextcloud configuration to implement that.
I would like to know if you can use a completely different URL for sharing as the one you use to open the Nextcloud instance.
No, that’s not possible because Nextcloud can only access files using its own context.