If Izuna Uchiha is out, which is a character from the Warring States Era, then Tobirama and Hashirama from Warring States Era should be out too.

What I would do if I am a Tencent character skill designer:

- Tobirama Senju (Warring States Era)

Attributes: Water, Konoha, Senju, Sword-bearer

#Mystery: Water Dragon Bite

Attribute: Nin / Water

B. Cooldown: 1 round

Cooldown: 2 rounds

Chakra: 20 points

Cause water attribute damage and interruption to a selected line of opponent's formation and cause repulse to the selected target and increase its mystery cooldown by 1 round. Then create a shield for self based on 30% Ninjutsu base attribute.

#Standard: Close Quarter Combat

Attribute: Tai

Attack enemy with the lowest health and cause tag with a fixed chance of causing 3 combos. This skill ignores enemy defense status (Like Hinata Trigram). Moreover, if an opponent's unit killed by this skill, Tobirama will launch another attack (can overlap with other extra attack buff).

#Chase: Flying Thunder God Slash

Attribute: Tai

Chase and attack repulsed unit and cause interruption and knockdown. This skill ignores a huge amount of defense and resistance, and will will never miss. If the unit has tag, cause critical damage.

#Passive1: Adept Sensor

For every unit on the opponent's field (including clones and summons), Tobirama will have 10% increase of evasion (up to 90%)

#Passive2: Sword Master

When battling against Sword-bearer Ninja, Tobirama will have his Ninjutsu, Attack, Defense, and Resistance increased by 100%.

- Hashirama Senju (Warring States Era)

Attribute: Earth, Konoha, Senju, Sword-bearer, Senjutsu User

#Mystery: Wood Golem

Attribute: Nin-Tai /Water-Earth

B. Cooldown: none

Cooldown: 3 rounds

Chakra: 60 points

Summon a Wood Golem with a same attribute as Hashirama (Wood Golem is immune to combo and debuff). This Golem is capable of attacking 4 units of your opponent's lineup. If the Wood Golem is already on the field, cause a great Water-Earth attribute damage to opponent's entire and knockdown to a selected unit while also causing immobile.

#Attack: Close Quarter Combat

Attribute: Tai

Attack unit in the front row with a chance of causing 5 combos and repulse. This skill has 100% increase of damage and will always critical against Uchiha ninja, but cannot kill a unit.

#Chase: Wood Style: Wood Bind

Attribute: Nin / Water-Earth

Chase and attack repulsed unit and cause knockdown while also causing immobile. This skill will never miss and can be triggered up to 3 times each round. Every time Hashirama triggers chase, recover 10 chakra points.

#Passive2: High-speed metabolism

Before the first action or each round, remove all debuff and recover 10% of life points and 40 chakra points. Furthermore, all units in your field will have their resistance increased by 20% and will recover 5% or life when attacked.

#Passive2: Poison Pollen Forest

At the beginning of battle, create a Poison Pollen Forest barrier. At the beginning of every round and at the end of every round, drain (not absorb, so both field are affected) 5 chakra points from each unit and cause poison. Lasting for 5 rounds.