I cannot answer for Taiwan, but if you're interested in an EU-based company registration from abroad, I recommend Estonia. The tax system is extremely straightforward: a company pays tax for its employee's wages (so, no tax for contractors, for example.) Flat rates, very easy to understand. In addition it's a very IT-based country; not relevant if you're not personally resident but worth being aware.

In my experience explaining the tax system here, which takes _less than a single page of text to understand_, generally blows most US citizen's minds :) It is very business-friendly.

Check the section "Estonian tax system" on this page: https://learn.e-resident.gov.ee/hc/en-us/articles/3600007215...