Before you try an experimental cutting, check to see if the variegation persists. The irregular pattern indicates a viral cause, and it must carry through to new foliage, not just on the parent stem, but to axillary growth, which is what you should take as cutting stock. Most viral variegation disappears fairly quickly.

I just witnessed a case of this variegation myself on a stock plant of Salvia puberula Yucca-Do form, but it did not persist. On the other hand, the irregularly variegated leaves of S. splendens vanhouttei Dancing Flames are stable. I haven't seen a reversion yet, and would like to see if seedlings revert.

One reason Salvia leucantha Eder does not sell well is that one of about 20 axillary shoots reverts, and since this reversion is more robust, it takes over. To succeed with Eder calls for at least weekly vigilance to cut off reverted growth.

Variegation that is similar from leaf to leaf is more valuable, since they are genetic, or perhaps epigenetic in origin and are more stable.