The Hidden Blade (2004)

Second film in the trilogy by Yamada Yoiji.

same director - same themes of love and difficult decisions about honour

They both have same director. They both deal with love and duty vs honour, and a lower caste samurai being asked to kill someone he is reluctant to.

It's part of the same trilogy and deals with the same troubles of poor insignificant samurai during the waning years of the class hegemony. I'd also recommend "Love and Honour" with KimuTaku, the third in the trilogy.

Both are based on fictions by Shuhei Fujisawa.

A 19th Century samurai, held in low esteem due to an action by his late father, must resolve his history with a maid and with his close friend.

The both protagonist are samurais, they seek avoid to use the violence, and both know great sword techniques.