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I believe that version of that device would be the Canadian version (SM-G781W). I understand it might use the same hybrid SIM/SD card holder as other dual-SIM versions, however, I don't think the Canadian version supports dual-SIM functionality (see here). In addition, as noted in the solution, that version does not support eSIM so it would not be able to use eSIM plus physical SIM either.
If you chose to purchase a version with dual-SIM capabilities, you should note that since that version is not available from Fido (ie non-Canadian version), it's likely certain features (ie voLTE and/or Wifi-calling) won't work.
Hope this helps 😀