If I visit Michigan, am a US citizen, am CHL in Texas, I know I can conceal carry in Michigan (reciprocity).
May I also open carry?
Short answer: Probably.
Long answer: MI Law states that you must follow the laws of this state when carrying, and that we honor the Texas resident CHL.
The Michigan law also states that you must also be in compliance with all restrictions listed on your CHL. So if your CHL says that open carry is not permitted with the license, you cannot open carry here. (Similarly, if it states that you cannot carry into, say, a grocery store on Tuesdays, you can't do that either, regardless of whether that's legal for a MI resident with their CPL).