I don’t know what you mean about “the newest Mesh router hub” in this context. If you are referring to the SmartThings WiFi mesh hub with plume, that’s actually an older hub model, and in any case is not needed.
The Aqara Zigbee sensors Can work directly with the smartthings regular V3 hub and its new replacement (no aqara hub required), the Aeotec “works as a smartthings hub“ but they are somewhat flaky. Popular, because they are so inexpensive, but they can require a lot of hands-on maintenance. And they do require custom code.
See the community FAQ
FAQ: Help! New to smartThings: will Xioami/Aqara sensors work?