  Fast neutrino flavor conversions (FFCs) and collisional flavor instabilities
(CFIs) potentially affect the dynamics of core-collapse supernovae (CCSNe) and
binary neutron star mergers (BNSMs). Under the assumption of homogeneous
neutrinos, we investigate effects of neutrino emission and absorption (EA) by
matters through both single and multi-energy numerical simulations with
physically motivated setup. In our models, FFCs dominate over CFIs in the early
phase, while EA secularly and significantly give impacts on flavor conversions.
They facilitate angular swaps, or the full exchange between electron neutrinos
($\nu_e$) and heavy-leptonic neutrinos ($\nu_x$). As a result, the number
density of $\nu_x$ becomes more abundant than the case without EA, despite the
fact that the isotropization by EA terminates the FFCs earlier. In the later
phase, the system approaches new asymptotic states characterized by EA and
CFIs, in which rich energy-dependent structures also emerge. Multi-energy
effects sustain FFCs and the time evolution of the flavor conversion becomes
energy dependent, which are essentially in line with effects of the
isoenergetic scattering studied in our previous paper. We also find that
$\nu_x$ in the high-energy region convert into $\nu_e$ via flavor conversions
and then they are absorbed through charged current reactions, exhibiting the
possibility of new path of heating matters.
