SARS, and SARS-CoV-2 are coronaviruses; bat rabies is a lyssavirus. The two entities are quite different in terms of structure, genetic code, mode of transmission, target cells and mechanism of disease. A recombinant merging the two is therefore unlikely. But more closely-related viruses can and do trade genes between themseves all the time. HIV is a good example.
Unlikely
SARS, and SARS-CoV-2 are coronaviruses; bat rabies is a lyssavirus. The two entities are quite different in terms of structure, genetic code, mode of transmission, target cells and mechanism of disease. A recombinant merging the two is therefore unlikely. But more closely-related viruses can and do trade genes between themseves all the time. HIV is a good example.