Hello,
Does the pass not show in the Wallet App on your Apple Watch or is it just not showing the notification? The passes from your iPhone should automatically sync to your Apple Watch. If you haven't yet check its settings.
Add and use passes in Wallet on Apple Watch - Apple Support
"Set options for your passes
- Open the Apple Watch app on your iPhone.
- Tap My Watch, then tap Wallet & Apple Pay."
Since a QR code is similar to a barcode this may apply.
- "If you have a barcode pass: Double-click the side button, scroll to your pass, then present the barcode to the scanner. You can also open the Wallet app
on your Apple Watch, select the pass, then scan it."
I hope this helps.