This problem is because some folder names on path flutter/cache/artifacts/engine is generated with x64 suffix and you need change each folder path error to correct path renaming each folder. For example I have executed on one project:

flutter build apk

and get that error:

Target android_aot_release_android-arm failed: ProcessException: Failed to find "/home/jose/flutter/bin/cache/artifacts/engine/android-arm-release/linux-arm64/gen_snapshot" in the search path.

For that I need rename the folder ending with "-x64" to "-arm64" to each error that you found after re-execute the build command.

After correcting each folder you can generate apk and bundle on arm64.

Here show some warnings after corrections but generated the "apk" correct.

Important that here I not using Termux I installed flutter on IOT device with Rockchip RK3588 and Ubuntu 24.04 and published article about that: https://medium.com/@joseph.ferg/flutter-android-development-on-rockchip-rk3588-devices-arm64-aarch64-7055edb5f14a