Mock images in NUV,u,ɡ,r,i,ɀ, and y bands for CSST (a) and in F070W, F150W, F200W, F182M, F356W, and F444W for JWST (b) generated from EAGLE simulation using GalaxyGenius. We notice that several companion sources exist apart from central targets. This is because that unlike TNG dataset, which stores its particle data based on individual subhalos, the particles retrieved from EAGLE are constraint by specific box length. Consequently, particles from companion sources are also included.