A: Thank you for these detailed questions!

Only one custom domain can currently be connected to your Introwise page. Increasing this number is an interesting feature - will take a note. But if you have multiple landing pages the best course of action right now would be to link your Introwise page directly (https://introwise.com/yourbusiness) from them.
The product is currently available in English only. The button labels customization is a good workaround for that, and we might look into it, but the localization of all interactions is not likely in the near term..
Pabbly Connect or Zappier are not supported at the moment, but it is a highly requested feature on our roadmap, stay tuned for updates: https://introwise.com/feedback.
We support customizations of your photo/logo, the cover image, the background color, and the buttons/accents colors. Custom CSS and HTML are not currently on the roadmap.
The custom domain currently applies to your booking page only, and the video calls are hosted on an introwise.com link. But we’re looking into ways to make the custom branding more consistent across all interactions, including hosting the calls on your custom domain.

I see that there are some repeating patterns in the requests around customizations, and that’s really important for us to hear that feedback to prioritize.

If you have more questions feel free to reach out to us via the website chat or send us an email at contact@introwise.com. We also host weekly Q&A sessions for our users, will be happy to see you there: https://introwise.com/introwise