Clarification needed on +x% Damage

Hi,

I was trying to optimize my generals and came up with the question, on whom the +x% damage is applied.

Example 1:

The unique item of El Cid gives 20% when leading Conquistadors. Is the 20% also applied on the other units when having 1 Conquistador in the team?

Example 2:

El Cid gets +5% damage (or even 10%) by gems when leading Mongolian Raiders. Is this damage applied only on Mongolian Raiders?

The castle displays always the same damage for the troops, so no help.

Best regards

Pug