In this anime you have a trio of classic samurai stories in Yotsuya Kaidan, Tenshu Monogatari and Bakeneko.
The weakest of the bunch by far is Yotsuya Kaidan. Which surrounds a story where a wife is betrayed by her husband as he kills her father. Eventually he sells Oiwa by eventually killing her so he can marry a granddaughter of a noble. On paper this story could showcase how one could be haunted by their decisions, as Iemori is haunted by killing Oiwa. Sadly, this is poorly done, especially with the side cast. Oiwa’s sister, especially, as her story was just idiotic.
Tenshu Monogatari was better as it centered around a samurai falling in love with a forgotten goddess. The writing around Tomi-Hime was great as it centered around her wanting to feel love, and possibly trading immortality for love is worth it. To add, there are consequences if she so desires to do it. Sadly, Himekawa’s character purely feels like a plot device and brings the story down a tad. But it is still enjoyable.
Bakeneko is the best of the bunch. It builds up the mystery well. One of the big themes that it executes well is the Mononoke/Bakeneko, who is the monster, but it is the humans who gave rise to it. As humans can truly be ugly creatures. This is pictured as an innocent cat turned into a monster, showcasing this well. Showcases the tragedy of the story well.
For a 2006 anime, the production for this is still decent enough. The OST is really nice. Honestly, if you are looking to watch Mononoke, I would just suggest watching the final 3 episodes that cover Bakeneko.