>>37451869In the official growth chart, it shows three evolutions that are just shown as question marks. As the Eevee Tama only just came out, nobody knows how to obtain them just yet.
There was a sales flyer that went out a few weeks before the Eevee Tama was revealed, showing the forms to be Eevee in a Team Rocket Hat, Eevee wearing a flower crown, and Ditto disguised as Eevee. However, lots of things shown on the flyer - including many of the sprites - are different from the final product, so we don't know if the three secret forms were changed too. 