= Eight-point isogenous elliptic curves over F5
{title2=$E_1(\mathbb F_5)\cong C_4\times C_2,\quad E_2(\mathbb F_5)\cong C_8$}
The <elliptic curves> $E_1:y^2=x^3-x$ and $E_2:y^2=x^3-x+1$ over $\mathbb F_5$ both have eight rational points. The first has four rational <2-torsion> points and the second has two, so their point groups are not isomorphic. They are nevertheless degree-two isogenous via $X=x+2/(x-1)$, $Y=y(1-2/(x-1)^2)$. The map sends $O$ and $(1,0)$ to $O$; its pole divisor for $X$ is $2O+2(1,0)$, giving degree two. Their <j-invariant of an elliptic curve> values are respectively three and one, so the curves are not geometrically isomorphic either.
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