I don't really see what they offer beyond what other tools provide but the terms of service is the first place to evaluate. From
https://face26.com/terms-conditions/:
"Unless you have advised Face26 otherwise in writing, you agree that we may use your images on our website (including a link to the homepage of your website) and in our marketing materials."
From
https://face26.com/privacy-policy/:
"We may also transmit your personal information with companies that help us to run our business by processing personal information on behalf of us for the purposes identified above. Such companies include providers of payment processing services, data analysis services providers, fraud monitoring and prevention providers, email delivery service providers, social media, and other marketing platforms and service providers."
"We may use third party track tools (such as Adwords, Bing, Facebook, Google Analytics, to track the information on how users use the products and websites, such information will be stored in third party servers. Such third party track tools may send the data analysis report for Face26`s above mentioned purpose."
None of these are surprising in any way and are highlighted to help people think about what they are agreeing to with a provider. They're very common provisos. It's one reason why I tend to prefer not using cloud tools for things like this. I use PhotosRevive and Topaz Photo locally for colorization and enhancements.