Hi Sergey,

Kindly find my response for your inquiries below:

is by any chance to add more social integrations except those in EasyBlog?

You can use sharethis or addthis https://www.screencast.com/t/Y3xGVawBu4qs
You can refer this documentation on how to setup sharethis : https://stackideas.com/docs/easyblog/administrators/how-tos/how-to-enable-sharethis

Can I integrate ok.ru?

Seems like this is still unavailable even in sharethis and addthis social button