Is there a reason this cannot be translated "את רואה אישה יפה" instead?
No. And it can also be "אתם רואים..." and "אתן רואות...". Report it.
יְפֵהפִיָה and יְפֵיפִיָה also means beautiful (as a matter of fact, יפה is more of a pretty then beautiful, while יפהפיה/יפיפיה is beautiful (feminine) and יְפֶהפֶה/יְפֵיפֶה means beautiful (masculine)