TL;DR - Too long, didn't read: Border agents have the upper hand, you can be detained and your devices seized. Key disclosure laws make it legal to force you to surrender your passwords and biometric access. Back up your devices, use encrypted cloud storage, wipe and factory reset your device, create new travel accounts, restore your devices when you reach a safe network.
https://www.privacytools.io/guides/phone-and-laptop-seizures-at-airports-and-borders
