The Aqara zigbee sensors work best with their own hub, and some models only work well with their own hub. But there are some models that can be connected directly to a smartthings/Aeotec hub, although they may require custom code, and the exact devices from other brands that you choose can affect the Aqara devicesâ efficiency.
So the first rule of home automation definitely applies: âthe model number matters.â
If you search the forum, you can find every possible answer to your question, because different people have had different experiences. 

Some people are using the Aqara contact and motion sensors with no problems as long as they have custom code.
Other people tried them, found they wouldnât stay connected, and ended up returning them.
If you can wait a few months, once matter is fully deployed, aqara is going to offer some of their hubs as âmatter bridgesâ and at that point you should be able to add the aqara sensors to their own hub and then bring that hub into the smartthings app. No custom code required. Just as people using Apple HomeKit can bring the aqara hub into the Apple home app today. (But adding to HomeKit doesnât give you smartthings integration. Iâm just mentioning it as an example of how the future matter integration should work.)
Anyway, as you can see, itâs pretty much a trial and error situation if you do want to try them right now without their own hub. And the best integration is with the simple door sensors and motion sensors. The other more complicated sensors, including the presence sensors, have less successful integrations.
I myself use aqara sensors with their own hub in Apple home and Iâm very happy with them. So I do like the devices, but Iâm not yet happy with the smartthings integration. 
Another Possible Future Option from Aqara
Another reason to wait is that aqara has announced that it intends to release a line of sensors that use thread instead of Zigbee. These will not need a hub, and as long as you have a thread border router, you should be able to add them directly to your smartthings account without needing custom code. 
So again, the model number matters.
Anyway, this announcement is very good news, but the thread sensors are not yet available.
https://www.aqara.com/us/news/article/1493841389451329536