Addendum, a possible solution for better collaboration between privately hosted Git platforms could be something like this: https://github.com/forgefed/forgefed (also based on https://github.com/go-gitea/gitea/issues/184 )
It doesn't solve the issue tracking part, however.
And in other news: https://www.theregister.co.uk/2019/10/31/notepad_china_spam/ Using code for political protest is taking things one step further...