Translation of "Co-founder" in German

And Hussain Yousif, a co-founder of Bahrain Online, who is also in exile, warns:
Hussain Yousif, Mitbegründer von Bahrain Online und ebenfalls im Exil, warnt:
GlobalVoices v2018q4

Our fearless co-founder Ethan, preparing for battle.
Unser furchtloser Mitbegründer Ethan, der sich zum Kampf bereit macht.
GlobalVoices v2018q4

Block was also a co-founder of the Berlin Secession, a movement similar to the Munich Secession.
Block war auch Mitbegründer der Berliner Secession.
Wikipedia v1.0

He was also co-founder and president of the Society of Prehistoric Archaeology of East Anglia.
Er ist Mitbegründer der Society of Prehistoric Archaeology of East Anglia.
Wikipedia v1.0