“…For a 2D system ( σ yz = 0, σ zx = 0), the MOE is also suppressed by some scriptO symmetries [e.g., scriptO may be M x , M y , C 2 x , and C 2 y ] as well as limited by some combined scriptTS symmetries [e.g., scriptS may be M z , C 2 z , C 3 z , C 4 z , C 6 z )] due to the odd property of σ xy under these symmetries . Hence, by breaking above symmetries, MOE may also emerge in more commonly available collinear AFMs. − From the nanoscience application perspective, it is much desirable to enrich the MOE family in 2D collinear AFMs because of the emergent valley-indexes, − layer physics, ,− and multiferroic order. − Importantly, it is highly desirable to realize the long-sought spin-splitting in 2D AFMs, which has triggered extensive attention recently benefiting from the versatile development of altermagnetism. − …”