Yes, that is a Spotted Lanternfly nymph, and they are present (and abundant) in most of Maryland at this point. You do not need to attempt eradication with insecticide (it wouldn't be achievable anyway, since many will be out of reach and any pesticide chemicals would affect other insects). Fortunately, they will not cause serious damage to plants (except in vineyards and hops farms). While early control efforts (squishing, trapping, etc.) were important to slow their spread, we're unfortunately well past containment at this point, since multiple states in the Eastern U.S. have populations of this insect.

Miri