Hello Aozpay,
it is possible to use external MOSFETs to increase Cell Balance capability of our BMS controllers. I have an example schematic with external MOSFESTs, unfortunately its confidential I am not allowed to share it publicly here in community. Please create a ticket or please contact a distributor AVNET. Their representative mentioned your company. I have shared the schematic with him.
With Best Regards,
Jozef