I am trying to understand how to construct an action using the superspace formalism for $\mathcal N>1$. I have read that this is quite difficult to do, so let's consider a simple example. Suppose I want to construct an action for $d=1$, $\mathcal N=2$ supergravity with an $\mathcal O(\mathcal N=2)$ local symmetry. Such an action might describe a massless point-particle with spin $1$; see [https://iopscience.iop.org/article/10.1088/1742-6596/1208/1/012006/pdf].

Question: How do I construct such an action with off-shell SUSY using the superspace formalism?

I am trying to understand how to construct an action using the superspace formalism for $\mathcal N>1$. I have read that this is quite difficult to do, so let's consider a simple example. Suppose I want to construct an action for $d=1$, $\mathcal N=2$ supergravity with an $\mathcal O(\mathcal N=2)$ local symmetry. Such an action might describe a massless point-particle with spin $1$; see https://doi.org/10.1088/1742-6596/1208/1/012006.

Question: How do I construct such an action with off-shell SUSY using the superspace formalism?