Many german customers are contacting us about the use of Google Fonts. My guess is some creative lawyer or webmaster is spamming all german sites, without actually checking if they use Google Fonts, offering their services to fix.
Classical scare tactics marketing.
Sparkle has not been linking to Google Fonts since 2018:
It’s also stated in the documentation:
“When used, web fonts sourced from Google will be embedded in the website for privacy and performance.”
In German here:
As the blog post above mentions, you can check your site through https://webbkoll.dataskydd.net to verify that it makes no connection to third party sites (until the cookie banner is accepted).