The free version may not be available on Blender Market due to no active subscription, but you can get it on our website.

https://levonotion.com/products/keyframe-collection/

In Blender you can't animate collection's visibility. You can only animate the visibility of individual objects in a collection.

This addon makes it possible to animate visibility of all objects in a collection using two buttons: 

"Add Keyframe" and "Delete Keyframe"

You can toggle the Visibility of a collection without using the Outliner.

You can toggle the Visibility of objects in a collection without using the Outliner.

Version 1:

• Initial Release

Version 2:

• Toggle visibility of objects in collection.

Version 3:

• Works with current scene irrespective of "Scene" Name
• Fix blender crashing with Toggle Visibility of objects in Render
• Add collection viewport and render toggle icons change