The Lead

Both stories are about set in the past (The Lead - 1976-1990s and The Stage - Republican Era)
Both are about Chinese Opera (Qinqiang and Peking Opera)
Both showcase the behind the scenes of a Chinese Opera Troupe.

Both are story centre on Chinese Opera, The Lead - Qinqiang and The Chanting Willows - Yue Opera.
Both are set in the past, The Lead - 1976 to 1990s and The Chanting Willows - 1990s
Both showcase the decline of Chinese Opera in the 1990s and the struggles that come with it.

They both feature a young person training to become an opera giant (over time, of course). An amusing aside is that they're both helped by a trickster elder to get started through sometimes nefarious means. But that doesn't mean they're not willing to learn their lessons (sometimes the hard way) and prove their talent. Basically, both HUGE OPERA DRAMAS ABOUT A SINGULAR TALENT. But slightly different time periods.