It is possible to integrate more than one selling channel from the same platform/source.
Each separate integration will be specified by a SubSource name to differentiate between the orders, listings, inventories etc. The name of the SubSource depends on the channel integration specifics: e.g. for eBay, the SubSource name is fixed and will be named after your eBay User ID, while for Amazon, the SubSource name can be added during integration yourself. Please refer to the documentation on Channel Integration for a detailed description of how to integrate each channel.
NB! When using an Amazon Unified Account, each country marketplace needs to be added as a separate integration. For eBay, the specification needs to be done only in regards to listings. Please see here for more details.
Please note that the SubSource names cannot be changed after the channel has been integrated. See this article for further details.