I think it's about establishing micro-forums to enable different provinces to talk to each other.
One of the things you could do is look at, for example, the Canada-U.S. Regulatory Cooperation Council. You could do something similar in terms of how different provinces focus on regulatory co-operation and interprovincial trade barriers. Have work plans and different principles the council could follow in order to ensure that where you have different priority items, you focus on what you can agree on for harmonized standards.
It's a collaboration effort. I don't think you need to be acting in silos to make that happen.