The specifics probably depends on your province, but there are laws in Canada similar to those in the US whereby a person receiving unsolicited goods and services to pay or return the goods. For example, the Ontario Consumer Protection Act, 2002 §13 says
(1) Except as provided in this section, a recipient of unsolicited
goods or services has no legal obligation in respect of their use or
disposal.
(2) No supplier shall demand payment or make any representation that
suggests that a consumer is required to make payment in respect of any
unsolicited goods or services despite their use, receipt, misuse,
loss, damage or theft
The BC Business Practices and Consumer Protection Act §12 similarly says
(1) A consumer has no legal obligation in respect of unsolicited goods
or services unless and until the consumer expressly acknowledges to
the supplier in writing his or her intention to accept the goods or
services.
(2) Unless the consumer has given the acknowledgement referred to in
subsection (1), the supplier does not have a cause of action for any
loss, use, misuse, possession, damage or misappropriation in respect
of the goods or services or the value obtained by the use of the goods
or services.
(3) Subsections (1) and (2) do not apply to goods supplied to a
consumer on a continuing basis under a contract between the consumer
and supplier.
(4) If it is alleged that the supplier supplied unsolicited goods or
services, the burden of proof that the goods or services were not
unsolicited is on the supplier.
Delivery is a service. It is legal to charge for customs clearance, so some somebody will be in the hook for the delivery. That person would be the sender, who did solicit the service. FedEx actually says
you can take advantage of lower clearance entry fees (CEF)*, which are
ancillary fees billed along with duties and taxes when you use the
FedEx International Ground brokerage-inclusive option. You have the
flexibility to bill the duties and taxes and CEF to the shipper,
recipient, or a third party. If the shipper or a third party is not
selected, the duties, taxes, and CEF will automatically be billed to
the recipient
but that does not invalidate provincial law pertaining to unsolicited goods and services. (Unsolicited means that you didn't solicit it, it doesn't mean you don't want it). Since you don't owe it, someone else is going to have to pay (though you may need to clarify to them the law regarding unsolicited services).