If you want to select ePacket as a global shipping method you can enable the option to ‘Select ePacket when available’ here here: https://app.dropified.com
For other shipping methods you can use Advanced Variant Mapping to map the AliExpress shipping options to Dropified. Dropified will then know which method to use when placing the order.
You can map these on a per product and per country basis.
Find this option under Variant Mapping > Advanced for any connected product in Dropified: