You are putting cart before the horses because optimizing for zero income doesn't make sense and you'll shortly understand why.
Just for the sake of conversation to identify the right country you need to
identify a country that has zero / minimum WHT on US royalties with no LOB, low CIT AND zero / minum WHT on dividends to your tax residency country
To this date you have few options:︀
1. Georgia: 0% WHT on US royalties + 15% CIT + 5% WHT on dividends︁ (possibily 0% if your tax residency country has a DTT with Georgia).
You'll need to︂ hire at least one manager in Georgia + rent office space
2. Romania: 10% WHT︃ on US royalties + 1% CIT up to 500K revenue (you'll possibly get a credit︄ for the foreign taxes paid) + 8% WHT on dividends (possibily 0% if your tax︅ residency country has a DTT with Romania)
You'll need to hire at least one manager︆ in Romania + rent office space
3. Poland: 10% WHT on US royalties + 9%︇ CIT up to 2mln revenue (you'll possibly get a credit for the foreign taxes paid)︈ + 19% WHT on dividends (possibily 0% if your tax residency country has a DTT︉ with Poland)
You'll need to hire at least one manager in Poland + rent office︊ space
Bottom line, even with credit for foreign taxes paid and 0% WHT on dividends︋ you're going to pay at least 10% tax + salary + office space + accounting.︌
For someone starting with zero income is a lot of expenses right out of the︍ gate.
Bonus option: by forming a US LLC and moving your tax residency to Georgia︎ you'll be tax free but this would require you to stay 183 days in Georgia️ to become tax resident and i'm not sure you want to to that.
You could stay less time depending on your home country ties.
