Based on your explanation:
You are correct that you will not be subject to British taxes, but will be subject to US taxes.
There is no need, whatsoever, for you to form any sort of company for this activity, it's perfectly legal to earn this money as an individual. It would not be legal, however, to treat this income as dividends. This is compensation for your time and efforts and, as such, is subject to Self-Employment tax reporting (the equivalent of Social Security).
You can treat this as 'Other Income' reporting it on line 21 on Form 1040 (unless they renumber the lines this year), but you will also have to include Schedule SE, to report the self-employment income and pay the related tax.
While I can see this increasing your tax preparation bill, I can't see it doubling the cost. If so, you need to find a new preparer as it will require only 2 additional items of data-entry and their software handles the rest.
FWIW, I am a tax advisor (for over 30 years). However, I must state that you cannot legally rely on this advise as I have not met with you and discussed this matter in depth.