The FP300 is Matter compatible, so not necessarily an Aqara hub.
Yes & yes.
Yes, it offers continuous reporting as shown in the short screen recording.
Yes, you can use this for automation. for example, I use it for controlling my heating in a room where I keep reptiles & tarantulas so the ambient room temperature stays within a certain range.
In addition, I use the light sensor to control a blind, the humidity sensor to control a misting device & the presence sensing to control a light. Not bad when it’s all done through one tiny sensor. you can view this post to see more -
or an extended look here. This link has a link to a video too big for the forum. -