Using Office-URI-Schemas to create a link for opening Word with an add-in open in the Browser (Office365)

I am currently developing an add-in that heavily relies on the possibility to provied a link for a customer, that automatically starts a word instance with that add-in open. I have already found the documentation for Office-URI-Schemas, and can successfully open a on-premise word instance with a registered add-in (ScriptLab). But there are 2 Questions that I can't find a definitive answer for:

Is there any way to create a link that opens Word-365 in the browser instead of the on-premise app?

It's important that this "link" also OPENS the add-in I specify, otherwise the workflow doesn't make sense. The link should also provide query-parameters that the add-in can read. I want the experience to be as similar to the on-prem version as possible. Since I can't find any documentation for an actual "link" doing this, maybe there is a way to configure the OS to treat commands that open the word app to redirect to the browser? Or any other way to satisfy the use-case of a customer clicking an interactive element in a cloud application and that leading to word opening with my add-in started in the browser.

I have found documentation about install-links, but these don't seem to directly open the add-in in the browser: https://learn.microsoft.com/en-us/office/dev/add-ins/publish/publish-office-add-ins-to-appsource#open-in-office-on-the-web

Is there a way to release/publish a add-in to the AppStore without it being visible to everyone?

For a link created with the Office-URI-Schemas to open a add-in, that add-in has to be registered in the AppStore, since the way it works is by providing the AppStore host and a appId in the link. I would like to release a dev/debugging version to test the behavior of the launch links, before it goes productive.

Environment:

• Latest version of OfficeJs
• Device targets: Windows, Mac, Android, IOS

Thanks in advance.