Dual-atom　catalysts　(DACs)　embedded　in　nitrogen-doped　graphene　have　been　widely　studied　for　electrochemical　CO2　reduction　(CO2R),　primarily　yielding　CO.　However,　achieving　selectivity　for　C1　hydrocarbons　remains　challenging.　Here,　32　Janus　DACs　(J-M＇M)　are　designed　and　investigated　for　CO2R　using　density　functional　theory　(DFT)　calculations,　identifying　13　capable　of　producing　methanol　and　methane.　Notably,　J-FeCo　and　J-CoNi　exhibit　favorable　limiting　potentials　(-0.38　and　-0.45　V　vs.　RHE)　for　CH3OH　and　CH4　production,　respectively,　based　on　constant-potential　calculations.　Compared　to　normal　DACs　(N-M＇M),　Janus　DACs　demonstrate　enhanced　initial　CO2　hydrogenation　and　stronger　CO　adsorption.　Oxygen　coordination　in　J-FeCo　and　J-CoNi　induces　a　downshift/upshift　of　majority-/minority-spin　energy　levels　of　d(z2),　d(yz),　and　d(xz)　orbitals　toward　the　Fermi　level　relative　to　N-FeCo　and　N-CoNi,　strengthening　the　bonding　state　and　weakening　the　antibonding　state,　thereby　improving　CO　adsorption.　Furthermore,　an　effective　descriptor　based　on　atomic　features　is　identified　to　evaluate　*CO　binding　strength.　This　work　highlights　the　critical　role　of　partial　oxygen　coordination　in　DACs　for　C1　hydrocarbons　production　and　proposes　a　robust　descriptor　to　guide　the　design　of　related　catalysts.