We use Google Shopping campaigns for all of our products in the webstore, but I am getting price mismatch errors on matrix items. The matrix items change the price based on the options selected, but Google shopping only sees the lowest price of the item. I think this is because of the way the SEO page generator works. Is there a fix for this? All of my items with matrix options that change the price of the item are being disallowed in Google shopping.

Out of the box, the microdata works "OK" at best. We found similar issues to what you've described However, in a more recent release 2020.1 (maybe one v. earlier??) it's my understanding that there was a change in microdata format to LD-JSON. Hopefully that change resolves the issue. We had already wrote our own LD-JSON module a year or so ago I can't say how the 2020.1 module works.

We don't use the base theme, so I can't even turn that on to test. But, I think moreso it has to do with the way the SEO page generator works. I don't think that Google uses javascript when crawling for prices.

Are you rendering any microdata?

It's not so much about the microdata, as it is the item options that are not coming over.

Not sure what else to say. We had the same problem (google was scraping our pages and was the getting wrong price for matrix children -- it would often pick the lowest price of all options). We implemented microdata, which updates on matrix selection, the problem went away.