This animation symbolizes the government changeover that followed the Boshin War. The first crest (3 leaves) belongs to Shogun Tokugawa, the subsequent crest (chrysanthemum) belongs to Crown Prince Mutsuhito who would later become Emperor Meiji.
In Blood and Tears episode 4 (18JUN18), Usaburo, O-Hatsu and O-Bun meet a tayuu who is part of a traveling theatre group that offers a variety show of sorts, which might include kabuki theatre, acrobatics, swordplay, dancing, singing, comedy, storytelling, etc.
I found a terrific video of a live kabuki performance of Kanjinchō 勧進帳 (The Subscription List), which is a favorite of yours truly. The play is listed among the 18 Famous Kabuki Plays (歌舞伎十八番) in the kabuki repertoire and still hugely popular to this day. The leading character is a fierce warrior named Benkei, regarded an exemplar…
In episode 6 of Blood and Tears, Usaburo received the gift of a small hand towel decorated with a print of contemporary actor Ichikawa Yaozo III. The print depicts him as the lead character from the traditional kabuki play, Treasury of Loyal Retainers (忠臣蔵 Chûshingura).
In Blood and Tears episode 7 (09JUL), Usaburo gives O-Hatsu a small lacquered storage box, called inro, bearing his family crest.
Episode 12 (13AUG) of Blood and Tears includes a map detailing troop movements during the Battle of Ueno. This graphic started with a woodblock print of Edo published in 1858—part of the Japanese Historical Map Collection housed at the C.V. Starr East Asian Library at the University of California, Berkeley.