[ElMiko]

you may want to be careful with the lowercase-upper separator, as it will match (and modify) body text such as "McDonalds" and html code such as "preserveAspectRatio" and "viewBox".

I use something like:

(?<!Mac|Mc)(?<=\p{Ll})\p{Lu}(?!spect|atio|ox[=])

to exclude false positives, but even then I correct each instance individually (ie, not in bulk), just to be sure.

you could add parentheses around "\p{Lu}" and set the replace value as "[blank space]\1", but again, i would still recommend cycling through each instance individually.