Are both

1 He hasn't still arrived
2 He hasn't arrived yet

equivalent and correct?

Anonymousequivalent and correct?
The word order is different.

1 He still hasn't arrived.
2 He hasn't arrived yet.
Students: We have free audio pronunciation exercises.
The first implies some expectation that he is late. The second does not necessarily imply this.
It turns out your father will have to pay.