  The state of supranuclear matter in compact stars remains puzzling, and it is
argued that pulsars could be strangeon stars. The consequences of merging
double strangeon stars are worth exploring, especially in the new era of
multi-messenger astronomy. To develop the "strangeon kilonova" scenario
proposed in Paper I, we make a qualitative description about the evolution of
ejecta and light curves for merging double strangeon stars. In the hot
environment of the merger, the strangeon nuggets ejected by tidal disruption
and hydrodynamical squeezing would suffer from evaporation, in which process
particles, such as strangeons, neutrons and protons, are emitted. Taking into
account both the evaporation of strangeon nuggets and the decay of strangeons,
most of the strangeon nuggets would turn into neutrons and protons, within
dozens of milliseconds after being ejected. The evaporation rates of different
particles depend on temperature, and we find that the ejecta could end up with
two components, with high and low opacity respectively. The high opacity
component would be in the directions around the equatorial plane, and the low
opacity component would be in a broad range of angular directions. The
bolometric light curves show that even if the total ejected mass would be as
low as $\sim 10^{-4} M_\odot$, the spin-down power of the long-lived remnant
would account for the whole emission of kilonova AT2017gfo associated with GW
170817. The detailed picture of merging double strangeon stars is expected to
be tested by future numerical simulations.
