Upon seeing your reply I actually thought of another work of animation that sort of fits that model - Mamoru Oshii's Angel's Egg. If you haven't seen it, it's slightly over an hour's worth of foreboding & atmospheric religious allegory charting the process by which faith is shaken and destroyed by doubt in a world suffocated by extremism. Beyond the fascinating nature of the movie itself, as an extremely uncommercial but beautifully produced (the art & animation were headed by Yoshitaka Amano) film with a necessarily limited audience in the highly commercialized world of anime, it's hard not to read the film as a very personal expression of a devastating religious crisis had by the director: he was in his youth a devout Christian, to the point of training for priesthood, before something shattered his faith and led eventually to his drastic career shift into animation.
What mostly comes to mind are the independent auteur projects produced by Art Theatre Guild, a production company that ran from the 60s to the 80s with a goal of distributing & sometimes financing films outside of the major studios in Japan and which constituted much of Japan's underground cinema of the time. You can read about them in an extensively detailed, though somewhat dry, article at
Midnight Eye if you desire; as for intensely personal and uncompromised visions with something of the auteur poured into them, as I believe unites your two examples above, the most immediate example I can think of would be Shuji Terayama's Pastoral: To Die in the Country, which is also coincidentally available on Youtube, or perhaps something like the grotesque Blind Beast or the kaleidoscopic mockumentary/parody Funeral Parade of Roses (also distributed by ATG, and on YT.)