My favourite examples are (in order) the Boogiepop Phantom OP, the headset POV from Lain, and the Instrumentality scenes from The End of Evangelion. The live action ending of Lucky Star episode 13 is interesting but is deliberately (comedically) unintegrated with the animated nature of the rest of the Episode. The live action sections of Otaku No Video structurally flow with each episode but aren't visually blended at all. And I like Hidimari Sketch's mix of live action footage and photographs with animation but im ideally looking for something played more straight. Thank You so much!!!

More blended - Kuuchu Buranko, Sarazanmai ED

More seperate and it is a comedy, so perhaps not what you're looking for, but I'll rec it because it is one of my favorite anime from the 2020's:
Gal to Kyouryuu - it is from the same director as Pop Team Epic and has some of that vibe if it was a lot slower and more nichijoukei. The episodes are half animated, half live action.
Thematically and narratively speaking, these two halves are generally related.

Yaku nara Mug Cup mo also has live action segments at the end of each episode with the seiyuu.

There are also a lot of anime that have short live-action post-ED scenes. Two that are sticking out in my memory are Arakawa Under The Bridge and Anyamal Tantei Kiruminzoo

OMG I DIDNT KNOW ABOUT ANY OF THESE BUT SARAZANMAI. Thank You, Thank You.

>>1
it's kind of a spoiler but there is live action stuff in SSSS Gridman

Fate Zero