Question

Identify the type of irony in this example “ extremely moderate”

Hyperbole

Paradox

Understatement

Answer 1

I think its a paradox because those two words have different meanings so much so that they are in most sentences antonyms. But when put together the prior word describes the latter word creating emphasis and effect.

But we can also say that its almost an oxymoron since two words that don't really belong together are pit together to create emphasis on the latter word. (Ie beautiful disaster.)

Answer 2

I believe the answer is Paradox, since "extreme" and "moderate" are rather contradictory.
Hyperbole is an exaggerated statement or claim.
For an understatement, you need to know the context of the phrase before determining whether it truly is an understatement (I.e. something that is underestimated or under-represented).

Hope this helps! :)