  The discovery of a charged strange hidden-charm state $Z_{cs}$(3985) implies
another higher $Z^*_{cs}$ state coupling to $\bar{D}_s^{*-}D^{*0} + c.c$ under
the heavy quark spin symmetry. In this paper we discuss a possible hunt for it
with data taken at existing facilities. We point out a hint for $Z^*_{cs}$ in
the data of $\bar{B}_s^0 \to J/\psi K^- K^+$ at LHCb, though weak, in line with
the production mechanism of pentaquark $P_c$. We also study the triangular
singularity which would possibly enhance the production of $Z^*_{cs}$ in
electron-positron collision. Surprisingly, the production rate of $Z^*_{cs}$ is
expected to be maximum at the $e^+ e^-$ center of mass energy of 4.648 GeV,
which is lower than 4.681 GeV for $Z_{cs}$ due to the inverted coupling
hierarchy of $D_{s1} \bar D K$ and $D_{s2} \bar D^* K$ in the triangle
diagrams. Their bottom analogue under heavy quark flavor symmetry is also
discussed. Our theoretical analysis would confront with future experiment of
LHCb, BESIII, and Bell II.
