Resourcing data from multiple cms sources

I have 2 CMS data structures.

CMS 1 = Brand and Brand Colors. ( 10 - 15 Brands)
CMS 2 = Product details ( preview image, rich text etc).

I am creating a product showcase grid.

The product showcase grid contains a product details card ( which links to the product details page), I want to show the preview image with the background color of the brand.

Since the brand is in a different CMS, I am not able to fetch relevant brand colors into the product preview.

Any idea on how to “nest” cms inside a cms while fetching data from parent cms ?

Here is my public share link: LINK
(how to access public share link)