Is the ME antenna far field radiation is similar to the conventional electric antenna？When the distance is larger than 2L²/lamda（wave length of EM wave）
No, it is larger. That definition is for the distance where the wave-fronts appear close enough to spherical for practical purposes, which is when the distance from all radiating points on the antenna to any single point on the sphere don't differ by more than 1/8 wavelength. For antennas that are smaller than a few wavelengths across, the reactive fields, that contain stored energy that doesn't radiate, reaches out a few wavelengths, resulting in the reactive near field, which has a larger radius than calculated by your formula. In this region transformer coupling or capacitive coupling would be more significant than radiative coupling.
These reactive near fields contain stored energy that is used (by Chu) to define the minimum Q or maximum bandwidth of a "small" antenna (that doesn't have any losses other than radiation or mismatch).
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