Moving to Taiwan with Chinese wife - what are the laws?

2013, and to be honest I cant remember every single detail. But I do remember that I just used my ARC and the documents that I had for my family. No third party guarantor. My dependents were residents of Mainland China.

The OP or anyone else in the situation can only know the requirements by contacting the national immigration agency. One thing I would say is that it pays to call in and be as polite as possible and keep on the lookout for a helpful immigration officer who is going to take ownership of your case and get you around the catch-22s . There may be some “computer says no” types there, just don’t lock horns, and try again till you get a helpful one.

Times of better relations. Yes, things have changed a lot since then.
I did run into one of those “computer says no” situations with the MOFA, but I was so lucky to get a truly kind person who woke up the boss, who was also really nice. Usually, if something CAN be worked out within the law, the NIA and the rest will eventually help you work through it.

They are still the same people, the helpful ones are still helpful. We had a overstaying catch-22 just this year and it was the same, they sorted us out.

Exactly, if you don’t blow your lid and your goal is achievable , then they will help you.

Man, this really blew up. Thanks for all the advice and experiences, everyone. Infinitely more helpful than I expected. I’ll be making some phone calls this week, it seems!

By law, yes. But technically, not true. There are, actually quite a lot of US-China dual citizens and the Taiwanese government knows this. The US doesn’t report to the Chinese government when one of China’s citizens becomes a US citizen and doesn’t require renunciation of Chinese citizenship to naturalise as a US citizen. So many people stay in limbo, some even travel back to China on their Chinese passport if not yet expired. Their Chinese citizenship is not cancelled until the Chinese government has evidence of their foreign nationality, commonly when they apply for a visa to visit China which is when they hand in their Chinese passport and their citizenship is cancelled.
I think it would be best for your wife if she can obtain some sort of certifiable proof that she lost Chinese nationality.