Impact of uninstalling installed package from production on sandbox?

Question

I have to remove all of the installed packages (mostly managed packages) from Production. Reason: Some of the packages are unwanted now and for others a different package version(not higher) is required.

Question:

1. Will there be any impact of it on any of the EXISTING Sandboxes where these managed packages are already present?
2. Will deletion from prod will automatically delete (same) installed packages from sandbox, or any other impact of such sort (be it on licenses or something)?
3. What are points we need to keep in mind while installing same packages again with different version?

In SF documentation, nothing of such sort is mentioned.

Note: Sandboxes, in our cases, comprises of all type of sandboxes (dev, dev pro, partial and full copy), And Prod is of Enterprise Edition.

Answer 1

1. There will be no impact on the Existing sandboxes where these managed packages are present. I think The changes will be reflected in the sandbox whenever you refresh the sandbox.
2. Deletion from Prod will not automatically delete the installed packages from sandbox.
3. If you are going to re-install the package, then you should take the backup of the following things:
   1. The configurations that you have done for the installed packages.
   2. Some code might be written on top of the managed package.
   3. Some objects or fields might be created on top of the managed package.

In short, while uninstalling the package, Salesforce will show the dependencies. You should take a backup of those dependencies.