For me it would be Princess Mononoke, which is also one of my favorite films, period. I really appreciate the maturity and nuance it brings to it's environmental themes, which have been done in many other films, but not as well.
Language is English but Japanese titles and short comments eg. “かわいい!” are allowed. This is because my Japanese is shit and thus I cannot moderate it effectively.
Princess Mononoke is my favorite for sure. I love the character design, the setting, the environmental storytelling. And wulfy
Besides that though…I really really liked Spirited Away. So rich and nuanced. I liked the twists and turns the film took