Controlling node's content using field setting
You don't need your own field types for this like comment adds.

You can use checkboxes, radios, lists, whatever you want that makes sense for you.

Moving them into the sidebar requires some form alter code in the node forms that moves them into fieldsets. path_form_node_form_alter() is an example that defines a fieldset and moves a field into it.

Then all that's left is custom preprocessing/twig checks.. check the value of those fields and then display whatever you want.