Even if the APK is not malicious, installing an unofficial port of a 3DS game can corrupt system files. The architecture of a 3DS (ARM11) versus Android (ARMv8-A) is fundamentally different without proper emulation layers.
If you want to play an Attack on Titan game on Android without the hassle of emulation or legal gray areas, consider the official mobile titles available on the Google Play Store: Attack On Titan Humanity In Chains Download Apk For Android
Avoid fake APKs at all costs. They are phishing scams. Even if the APK is not malicious, installing
Yes to emulation. Attack on Titan: Humanity in Chains remains one of the best handheld AoT experiences. Playing it on a high-refresh-rate Android screen with an upscaled resolution (720p → 1080p) is arguably better than the original 3DS version. If you want to play an Attack on
Final recommendation:
Since there is no native Android port, you must use an emulator. The most reliable 3DS emulator for Android is Lime3DS (formerly Citra MMJ).