One is the famous koan where Nansen kills a cat when no monk could answer his challenge. This suggests that, in the right situation there is a “nondual” kind of killing that is in accord with the Zen interpretation of Buddhist precepts.

The other point is that, whether or not such a reading is justified, it was certainly used widely during the second world war to add a spiritual and ethical dimension to combat. Most American Zen students do not realize that some of the major teachers who brought Zen to the West in the postwar teacher were either influenced by or were themselves monks who spoke out openly in favor of the war and provided spiritual ideological support for killing. Suzuki himself was quite a nationalist. This sobering tale is well told in Brian Victoria’s book Zen at War.

I am not sure if you are asking about samurai women in film roles or in history? I will assume the latter. There are some stories of heroic samurai women (daughters, wives, sisters of samurai). Two in particular come to mind from the present exhibition.

One is about Hosokawa Gracia, the Christian wife of the warrior Hosokawa Tadaoki who preferred to die rather than be taken hostage by her husband’s opponent. A bell for a church commissioned in her memory is in the exhibition.

Another famous story of a samurai woman is depicted in a painting in the exhibition. It shows Tomoe Gozen in full armor on horseback carrying off the head of one of her enemies. Here is her story on wikipedia

Also, check out this article on women warriors of Japan. In it the author questions whether Tomoe Gozen was a real person.

This is not the most definitive answer to your question, but may get you pointed towards some interesting reading. Whether she was real or not, Tomoe’s story was hugely popular, appearing in the Tales of the Heike and in countless woodblock prints and paintings–see the images that came up in a Google image search.

My understanding is as follows. The word samurai is used differently in English from the way it is used in Japanese. In the original Japanese usage, samurai were lower-level members of the warrior class. Miyamoto was a bushi, but in English the word samurai is applied to warriors of any status — even though this would be incorrect in strict Japanese usage.

A lower-level warrior/samurai who lost his master would become an unemployed warrior (ronin), but would not cease to become a member of the warrior/samurai class. Of course, at the end of his life Miyamoto served under the Hosokawa, so he was not always masterless.

Of course, almost all of the qualities that typify Zen practice and life (except for the not killing part) would benefit a samurai, and it makes sense that samurai would draw from this deep reserve, but I question whether the life of the samurai and that of the Zen practitioner are fundamentally, philosophically, practically compatible.