In 2012 [I was porting OpenEmbedded to target AArch64]( so I can say that I did first OE builds **for** that architecture.

But today I did kind of reverse thing:

Build Configuration:
BB_VERSION        = "1.21.1"
BUILD_SYS         = "aarch64-linux"
TARGET_SYS        = "arm-oe-linux-gnueabi"
MACHINE           = "genericarmv7a"
DISTRO            = "nodistro"
DISTRO_VERSION    = "nodistro.0"
TUNE_FEATURES     = "armv7a vfp thumb neon callconvention-hard"
TARGET_FPU        = "vfp-neon"

Yes — I did build **on** AArch64 machine targeting ARMv7a system. Had to edit one patch (pseudo-native was set to use very old glibc symbols which are not available on 64-bit ARM) but after that build was running just fine.

I did not tested resulting binaries.

AArch64 can build OpenEmbedded