If this is any help, I know that some records of Hanoverian soldiers in
the service of King George of England, also Elector of Hanover, exist in
British records, for what is known as The King's German Legion.
I looked at these myself recently seeking an ancestor, and they mainly
consist of Muster books for pay purposes.
Printed lists of soldiers serving in this regiment are at the National
Archives library in London, and are mostly I think for those at