Hi hot_spur,
welcome to the Apple (user-to-user) Community!
Re: Wayfinder night vision mode : Now you have to actually edit the watch face to engage it.
Seems the answer may be to add the Wayfinder watch-face to your collection of watch faces, so you can just swipe between watch faces as required.
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To choose a different watch face on Watch Ultra:
Touch and hold the watch face, swipe to the one you want, then tap it.
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To add a watch face to your collection
Create your own collection of custom faces—even variations of the same design.
- With the current watch face showing, touch and hold the display.
- Swipe left all the way to the end, then tap the New button (+).
- Turn the Digital Crown to browse watch faces, then tap Add.
- Tip: Tap a collection such as New Watch Faces or Artists to browse a specific category of watch faces.
After you add it, you can customize the watch face.
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There's a short "YouTube" (non-Apple) video online that may help add / set-up the Wayfinder watch-face:
https://www.youtube.com/watch?v=lPeIiai6Svs
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To View your collection of watch faces:
You can see all your watch faces at a glance.
- Open the Apple Watch app on your iPhone.
- Tap My Watch, then swipe through your collection below My Faces.
To rearrange the order of your collection, tap Edit in My Faces, then drag next to a watch face up or down.
You can also rearrange the order of your collection on Apple Watch Ultra. With the current watch face showing, touch and hold the display, touch and hold again, then drag the selected watch face left or right.
More watch-face info. and details: Change the watch face on your Apple Watch Ultra - Apple Support
All the best :-)