21 down - A singer upset to be punched by unknown French lyricist (5) - T?A?A I think it’s Tzara (as in Tristan - French lyricist), but I can’t quite reason out the rest of the clue, except for “z”...
1 across - Initially trained in a southwestern city, she wrote most famously about Yorkshire (6) ???T??
and
21 down - Trollope's lady who returns from Essex? (5) O????...