Coleus sounds like a stretch but it would be fascinating if it worked.
I would more expect people to try grafting to Salvia splendens.
If I were to try grafting S. divinorum to anything
or hybridizing it with anything my first attempt would be pairing it with Salvia tiliifolia.
S. tiliifolia is related to S. divinorum and a native of central america, it has the same chromosome count as S. divinorum, it is variously described as either an annual or a zone 10 perennial (so its probably the latter) and seems to flower easily, I dont know about the leaves but the seeds are roasted and brewed into a beverage.
I was going to try it at one point but every time I grew S. divinorum my agricultural district was hit by either a plague of thrips or a root-rot disease and the Salvia died