Is the second completeness axiom for V really needed for Ackermann set theory to interpret ZF?

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If from the axioms of Ackermann set theory we remove the second completeness axiom for $V$, and replace it with an axiom of power sets in $V$, that is:

For every element $x$ of $V$: the class of all elements of $V$ that are subclasses of $x$, is an element of $V$.

Formally this is:

$\forall x \in V \ \forall y \ [\forall z (z \in y \leftrightarrow z \subseteq x \wedge z \in V) \to y \in V]$

where: $z \subseteq x \iff \forall m \in z (m \in x)$

Note: the second completeness axiom for $V$ is the axiom:

$\forall x \in V \ \forall y \ (y \subseteq x \to y \in V)$

Question: Is the resulting theory still capable of interpreting ZF?