Acumatica is working on expanding this area of the product and we are looking for customers whom are interested in working with us and piloting such functionality in their environment. The goal is to include advanced capabilities that go well beyond simple predefined set of substitutions and upsell/cross sell possibilities for a given item. We are looking to incorporate smart substitutions based on substitution history, cost considerations, inventory levels, user selections in prior order entry/checkout sessions, using ML technologies.
If you are interested, please post here and one of our team members will get in touch with you to discuss this further.