Do 2018 MVPs need recommendations from Sitecore MVPs or Sitecore Employees?
How this process works for current MVPs?
As far I know current MVPs doesn't need recommendation this year.
Existing MVPs will receive an email automatically inviting them to create an acount, they do not need to be nominated by another MVP or Sitecore employee.
They need just to login on https://mvp.sitecore.com/application and they need to apply for Sitecore MVP 2019.