Sonia is from Sierra Leone, West Africa [or has Sierra Leone ancestry].
She soon proved to be one of the most talented, and popular, of all the Festelle girls; and she had some memorable battles with another black girl, Sherry. Sonia won most, if not all, of those matches, due to her strength and powerful arms and legs....and Sherry was certainly no slouch when it came to wrestling! This was when Festelle was an entirely OK organisation, rather than the German one that it is now.
I think she "retired" a few years ago; and then did private matches in her own home. I'm not sure if she is still active...but, if you "Google" her name, it may tell you. I don't recall seeing any of her matches on Youtube, but it could be that like another great Festelle wrestler, Jill Munro, there are some tucked away somewhere.
If you "Google" ...Diana the Valkyrie....there's just a chance that some of Sonia's matches maybe on there.
Sorry this is not more helpful.
GG