Structures that appear in Creative mode do not appear in Survival mode, for the same seed.

This is similar to MC-134729, but with the variant that I have two saves of the same seed (one with creative enabled, one with survival only)

Seed - 3276748543811363333

I have two worlds using the same seed. In creative, an end city generates at 1344, 368. However in Survival nothing appears.

I have inconsistently encountered this issue with other structures in other seeds. For example, this seed (-955523361464072251) a woodland mansion may or may not appear at -450 320 (survival mode). This is a good testing seed because the mansion is so close to the initial spawn point.