you can change all zombie to do what you want in XML files
for their health you can change that right there on Entityclasses.xml,
it would look something like this
<effect_group name="Base Effects"> <!-- zombieTemplateMale -->
<passive_effect name="HealthMax" operation="base_set" value="150"/> <!-- Zombie Health -->
<passive_effect name="HealthMax" operation="perc_set" value="1"/>
just change the value of Health Max (Base set)
for the block damage/Damage to player you would go to each zombie in the Entityclasses.xml and search for their "hand item"
it would look like this:
<property name="HandItem" value="meleeHandZombie01"/>
* if a zombie doesnt have a hand item it goes off of the zombieTemplate which is the one above and also some zombies have their own special Hand item*
from here you go to the Item.xml and search for the correct hand item (copy and paste)
for the one above this is what it says
<item name="meleeHandZombie01">
<property name="Extends" value="meleeHandMaster"/>
<property name="CreativeMode" value="None"/>
<property class="Action0">
<property name="Buff" value="buffInjuryBleeding,buffIllInfection0,buffInjuryStunned1"/>
</property>
<effect_group name="Base Effects">
<passive_effect name="ModSlots" operation="base_set" value="0"/>
<passive_effect name="EntityDamage" operation="base_set" value="25" tags="primary"/>
<passive_effect name="BlockDamage" operation="base_set" value="15" tags="primary"/>
<!--<passive_effect name="AttacksPerMinute" operation="base_set" value="75"/> A16 .8 -->
<passive_effect name="BuffProcChance" operation="base_set" value="0.15" tags="buffInjuryBleeding"/>
<passive_effect name="BuffProcChance" operation="base_set" value="0.10" tags="buffIllInfection0"/>
<passive_effect name="BuffProcChance" operation="base_set" value="0.15" tags="buffInjuryStunned1"/>
</effect_group>
</item>
you just change the values of Entity Damage (player damage) or block damage (building damage) to what you want
I am not sure if there is a MOD for this out there but if you wanted to change it yourself, thats how
*as always, make sure you save the original XMLs somewhere just in case*