Question regarding Required Acts of Wudu per Zaydiyya for Imami Convert

Thank you for your questions!

Because of very clear texts mandating the completion of ritual purity and since it is a pillar of the prayer, differences of opinion regarding it are considered serious. Insomuch that other seeming differences among other madhaahib are disregarded, however, ritual purity and prayer times are non-negotiable. This is also why we can't pray behind an imam who wiped the leather socks but can pray behind an imam who sees such as valid. 

As you said, a Zaydi can pray behind a Hanafi imam irrespective of what the imam believes regarding an obligatory or sunnah act of ritual purity. However, a Zaydi would be prohibited from leaving out those actions considered waajib in the madhhab. The issue of wiping vs washing the feet is a bit different because it--at least according to the Zaydiyya--is a matter of consensus among the Ahl al-Bayt as well as seen as being the apparent and explicit text of the Qur'aan, which leaves no room for ambiguity or disagreement. The other issues you mentioned--wiping the entire head and ears as well as rinsing the nose and mouth--were moreso derived from the Qur'aanic text and Prophetic traditions. 

And Allah knows best!

IRS