i2c workaround?

Some days I think my tenacity is more of a hinderance then a blessing.
Despite knowing i2c isn’t going to work, and that I should be focusing on using the RxTx Serial communications to transmit info between the Uno and NodeMCU, I can’t stop thinking about how to work around this and use the i2c bus anyways… and I have come up with a possible solution to explore… While communication is one way between the computers themselves (as the NodeMCUs can’t be seen) , all the sensors are still visible to all computers at all times.
I’m wondering if I could connect a DAC or 2 (one on each?) and use those to communicate via the Analog ins/outs on a regularly scheduled interval/cycle.
Will have to investigate… Man if that works… Hot Damn…