ITMS-90747 Architecture incompatible with MinimumOSVersion

I recently upgraded my project's deployment target version to iOS 12.0 and started getting warnings saying:

ITMS-90747: Architecture incompatible with MinimumOSVersion. The app bundle at 'MyProject.app/PlugIns/StickerPack.appex' specifies a MinimumOSVersion of '12.0' but contains a 32-bit architecture that is unsupported on iOS 12 and later.

I did some research and found a few people having the same issue, one common suggestion is to lower the project's deployment target version, this isn't possible for the main target because I have a few libraries that have minimum OS version requirements. So I wonder what should be the right way to fix this, so far I can think of two solutions:

1. The Message Extension target's Architectures is currently $(ARCHS_STANDARD) which translates to (arm64, armv7), so I can change it explicitly to arm64 only, or add armv7 to Excluded Architectures which sounds better.
2. Change the iOS Deployment Target to some version lower and do this only for the Message Extension target.

I'm going to try each of them and see what happens, but just want to ask do they sound like proper solutions or just workaround? Is there a better way to solve this?

Thanks!