since the beginnning of the year 2019 the Season system has been leaked with all four Ninjas that will exist.

Spring = Shira

Hints for Shira:

1. male

2. can not use Nin-Jutsus

3. Sand Ninja

4. Seaven heaven breathing method

Summer = Shizuka

1. female

2. princess

3. engaged

4. Nadeshiko Village

Autumn = Guren

1. female

2. Kekkei Genkai

3. Sound Ninja

4. Camellia

Winter = Chiriku

1. male

2. Land of Fire

3. Twelve Guardian Ninja

4. 30.000.000 head money

in this video u can see it also

https://www.youtube.com/watch?reload=9&v=aeHY2NDZNIs

btw in some other country Yota is also a mysteroius season Ninja for Autumn

some new Ninjas that exist will be first a ninja in 3vs3 to get them till 3 or 4 stars and then later a season ninja to upgrade them to 5 stars

Kinda weird we get 2 ninjas we dont have and 2 ninjas we already have. Is the autumn version of guren going to be her younger self? They seem to have that trend going right now.

Its literally the Guren we already have in game.

Yota, Hirashi are coming up also for the next few seasons, but that could change.

I hope we get Yota instead of Chiriku. :/