It's a very complicated bug for me to understand why it happens that every new 'Sovereign' leader has the 'Cruelty' icon with the 'Malevolence' tooltip. Actually all leaders you can recruit has many traits. But there are specific traits for governors, for diplomats, for citizens, for units and for leaders. They are all named like this in the LeaderTraitText.XML (leader_trait, unit_trait, citizen_trait etc.).
So what we see is that only the sovereign leader, which is actually assigned as your governor while playing with a custom civ always have the malevolence trait. While it's unclear for me if 'malevolence' is a used trait at all or something from the past.
What I see is when I search for 'malevolence' trait in the LeaderTraitText.XML file I only find this one:
<StringTable>
<Label>UnitTrait_Focus_Name</Label>
<String>[ICON=Cruelty_Icon] Malevolence</String>
</StringTable>
<StringTable>
<Label>UnitTrait_Focus_Dec</Label>
<String>Increases Malevolence ideology and +2 Diligence</String>
</StringTable>
So it seems the wrong description on the tooltip is from the above string. But the icon shown is the Cruelty_Icon from the GFX>Stats folder.
<UnitTrait>
<InternalName>UnitTrait_Focus</InternalName>
<DisplayName>UnitTrait_Focus_Name</DisplayName>
<Description>UnitTrait_Focus_Dec</Description>
<Icon>CrueltyIcon.png</Icon>
<Stats>
<EffectType>Diligence</EffectType>
<Scope>Local</Scope>
<Target>
<TargetType>Unit</TargetType>
</Target>
<BonusType>Flat</BonusType>
<Value>2</Value>
</Stats>
<Triggers>
<OnEvent>OnRecruitLeader</OnEvent>
<Target>
<TargetType>Faction</TargetType>
</Target>
<Lifetime>Instant</Lifetime>
<Modifier>
<EffectType>IdeologyProgressivism</EffectType>
<Target>
<TargetType>Faction</TargetType>
</Target>
<BonusType>Flat</BonusType>
<Value>1</Value>
</Modifier>
</Triggers>
<Preclusions>
<UnitTrait>
<Option>UnitTrait_Pacifism</Option>
</UnitTrait>
</Preclusions>
</UnitTrait>
There is indeed a UnitTrait named Focus in the LeaderTraitDefs.XML, so I suppose this is related. On the other hand, in that case, I don't know if it is intentional that all new custom sovereign governor leaders has the (non-working) Focus trait.
Sovereign trait for example is a Leader Trait and not a Unit Trait. And there is also a Leader Trait names Focused (not Focus).
So I want to know what do sovereign governor leaders are supposed to have for kind of traits at start?