Want to connect two BT earbuds at the same time

Was wondering if there is anyway around not being able to connect two bluetooth devices "of the same type" to my Nexus 6P?

For example, my wife and I want to listen to an audiobook playing from my Nexus 6P on our own separate bluetooth earbuds. It appears this is not possible.

I know it is possible to connect two bluetooth devices of "different" types, such as earbuds and a wireless keyboard, but it appears you cannot connect two of the "same" type.

Any apps or workarounds for this?

And, is this a limitation of the Nexus 6P? Of the operating system (I am also using Android O beta, and same problem)? Or a limitation of Bluetooth protocol?