Tools for overcoming differences in company/country cultures

I'm working closely with another office in another country that used to be another company that was bought a couple of years ago. Understanding how we can together effectively has been challenging, with lots of misunderstandings, time wasted and heated meetings.

What tools have you used to try and help each side understand how to work and communicate effectively?

I have used the following so far: https://hbr.org/2017/07/being-the-boss-in-brussels-boston-and-beijing https://www.hofstede-insights.com/country-comparison/