We had the same request from our clients over and over, until our development team rolled up their sleeves and they implemented the second UOM conversion. You can read how we handled it on this link: https://blog.erpag.com/2018/09/erpag-5.html

Our software also integrates with QB Online: https://blog.erpag.com/2018/09/quickbooks-online-erpag-manufacturing.html