I think there's a chance of MK8 Wii U & Switch outselling Wii Sports, but it would be by the slimmest of margins.
~51 or 52 million by the end of this year
~60 million by the end of 2023
~65 or 66 million by the end of 2024
Would still need about 8 or 9 million through the remainder of its life.