Tracy Chapman - Similar artists & their albums

She’s great. I just introduced her to a 50 something friend. I was surprised he didn't know of her

Maybe you'll get some ideas here - https://www.allmusic.com/artist/tracy-chapman-mn0000016281/related

Phoebe Snow. Despite having more of a fusion jazz style her lyrics are quiet and intricate which demand time from the listener similar to Tracy Chapman.

Phoebe Snow was a great artist. Like Tracy, she was unique, not an imitator. 

+1 Joan Armatrading. Her self-titled 3rd is a career highlight(especially the super analog recording on vinyl). Both of her compilations, Track Record and The Very Best of would serve as tremendous introductions.

Maybe a bit of a stretch, but another quite original artist, with great songs, authentic reproduction, upfront vocals and lovely acoustic guitars featured in many songs is Gillian Welch. Time(The Revelator), Soul Journey, and The Harrow & The Harvest are all excellent albums. Cheers,
Spencer