Who made the migration did a number of mistakes, I suspect an amateur or very unknowledgeable dealer, this is a bad migration, a forklift will not work, you need to plan it pre and post migration! They should first update EA from 2.10.x to 3.1 then to 3.3.1 to check if there are any issues with your drivers, devices, etc. then afterwards, another migration to Core 3.
Why you say memory? How do you know that?
Core can handle both ZB and ZW no issues at all, also who said all your ZW devices will work with Core?