It is a big limitation that Matomo only tracks three things at the product level.
"Because we have a very specific business, our __ products are quite complex. As a consequence we need to track a lot of data related to them in order to build some custom reports or build some benchmarks. Related to products, I only found the 3 very classical dimensions Product SKU, Product Name, Product Category and I did not manage to find a way to push more product attributes. "
"Is it possible to define custom dimension at product level ?"