when I see that whichever instance I choose is defederated from another bunch of random instances, is it possible to have those show in my feed without making a separate profile from other instances? and can I turn them off again if I see that defederating was the right idea?
You could host your own instance, that way you're completely in control. I'm also doing that, just because I don't want people(mods, owners) to decide for me who I interact with or not.
is there a way to refederate instances just for me?
when I see that whichever instance I choose is defederated from another bunch of random instances, is it possible to have those show in my feed without making a separate profile from other instances? and can I turn them off again if I see that defederating was the right idea?