How do I make this sentence sound better?
Some suggestions...
- use antecedents for pronoun (they) or remove it. ("John and Mary both... / Both agree...")
- replace agree with a stronger verb
- wields... mistakenly is an uncommon adverb pair, I am guessing. Look for a more specific modifier ("carelessly", "crudely", "foolishly", etc.)
Just variants. "Better" is not a clear figure of merit with soft arts like language. Except for maybe the 3rd point, which you might be able to demonstrate with a corpus ngram
They both agree that Athens wields and uses her power mistakenly.
Note I answered this question before it was edited.
First, I assume Athens references the city state of Athens. Secondly you have used the female form for the city I have seen this done numerous times in Historical texts/stories but it is not necessary. Thirdly presumably we Know who "they" are. Hence we can remove Both from the sentence. Finally as I have no context I am unsure of the tense to be used. It sounds possible we are talking about something that has already happened.
They agree(d) that the power and influence of Athens is(was) misused.
misuse Cambridge English Dictionary noun/verb to use something in an unsuitable way or in a way that was not intended:
Example There were suggestions that the articles involved the misuse of historical concepts and their evidence was wrong.