Any good resources on how to run a multivariate test (A/B test) where the IV is upstream but DV is downstream in a eCommerce funnel?

For example:

Imagine an eCommerce funnel that constitutes a configuration page, a bag page, a shipping page, a payment page and finally an order confirmation page.

You plan on running an A/B test in the product configuration page (example: 2 different messaging + control for selecting a financing option in the configuration page). Business wants to measure the impact of this test on downstream KPI: In this case it’s the conversion rate (how many people land on order confirmation page). …

bag b test datascience ecommerce example good imagine multivariate page payment resources running shipping test