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jmc
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No. Here is a counterexample:

  • Take $G = \mathbb{Z}/4\mathbb{Z}$, and $H = \mathbb{Z}/2\mathbb{Z} \times\mathbb{Z}/2\mathbb{Z}$.
  • Take any bijection $\phi \colon G \to H$ such that $\phi(0) = (0,0)$.

There are only two proper subgroups of $G$, namely $\{0\}$ and $\langle 2 \rangle$. Both are mapped isomorphically to a subgroup of $H$. But $G \not\cong H$.

So you will need more assumptions. Maybe the requirement that $\phi$ induces a bijection on the lattices of proper subgroups of $G$ and $H$?

jmc
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