The terms "liberal" and "conservative" have become almost emblems of tribalism rather than having precise meanings concerning political philosophy. There is a wide spectrum of conservative beliefs, with some conservatives supporting criminal justice reform and some opposing it. How a conservative would respond to such a call depends on the type of conservative.
Social conservatives see politics as a way to uphold a social order. Some such social conservatives see the purpose of criminal justice as punishment or inculcation of moral values by strict rules with harsh deterrents. They would tend to see criminals as "evil" or "bad" people who should be incarcerated to avoid contaminating others.
Another major thread of conservative thought is Libertarianism, which aims to minimize government interference in private lives. Libertarians do not believe victimless crimes should be illegal at all and would like to reduce the scope of government. Since restorative justice allows the criminal to make reparations to the victim or victim's family with minimal long-term government interference, libertarians might support it.
Another conservative group is deeply religious. As forgiveness and charity are an important part of many religions, as is the concept of repentance, many deeply religious conservatives might support certain form of restorative justice.
Another group of conservatives are basically business-oriented pragmatists. Such conservatives would look at two issues, the costs of incarceration and the likelihood that people would re-offend, and choose whichever system was actually more effective in reducing costs and recidivism.