There actually was a fair bit of research on dynamically loading hardware modules into FPGAs on the fly going all the way back to the '90s. IEEE's International Symposium on Field-Programmable Custom Computing Machines (http://fccm.org/2016/previous.html#past) had a "Run Time Reconfiguration" section in the '90s that's specific to papers that use that mechanism.

It's nice to see that research is still advancing in this area.