Dr. Bilal Philips says that those who follow the Zaydi math-hab are considered Shia’ but are very much similar to ahlus sunnah.

How is this possible considering that the Shittes have ‘aqeedah issues?

The main difference between the Shia’ and Sunni way is on ‘aqeedah.

‘Aqeedah itself is a very broad topic which includes infallibility of ‘Ali, the status of ‘Ali in Islam, the coming of the Mahdi and many other things which are not linked to ‘Ali.

The Zaydi’s do share some beliefs with ahlus sunnah, like on the infallibility of ‘Ali, but they do have some similarities with the Shia’, for example, the Imaamat and other issues which are part of ‘aqeedah. This has made it possible for the scholars to regard them as Shia’ and not as ahlus sunnah wal jam’ah.[1]

Only Allah Knows Best.

Reference:

[1] Ibn Hazm, Al-Fasl fil Milal, 1/12