Hi,
Zona Alfa and it's solo/co-op supplement Kontraband use a D10 dice mechanic.
The free supplement, Lone Wolves, was put together early in the lockdown right after the ZA's release.
Kontraband was developed later and is a larger, more refined supplement.
Exploit Zero (formerly known as Hardwired) Nightwatch, and Insurgent Earth use a completely different system. (D6, D8, D10 polyhedrals)
That were all designed specifically to be solo/co-op play.