QB Issue Resolution:

Sorry, there is no conversion path.  You should contact Intuit (assuming you purchased 2018 from them) and ask for a refund, then purchase the Canadian version.

While you’re at it, you might want to ask Intuit to upgrade your 8-year-old file to prevent problems on your end.

Resolution for Issue 'Can Quickbooks 2018 be upgraded to include Canadian files?' available: Yes (Solved).
Source: Intuit Community forum.

Can Quickbooks 2018 be upgraded to include Canadian files?: this issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the issue yourself by looking for a resolution described below. If it is a complex issue or you are unable to solve the issue, you may contact us by clicking here or by using other support options.

Support for Canadian files
Quickbooks Repair Pro will resolve it efficiently and affordably. Guaranteed resolution of your issue, or you pay nothing!

Error Recovery for Canadian files [Canada]
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