  We present the formalism for consistently transforming transition operators
within the in-medium similarity renormalization group framework. We implement
the operator transformation in both the equations-of-motion and valence-space
variants, and present first results for electromagnetic transitions and moments
in medium-mass nuclei using consistently-evolved operators, including the
induced two-body parts. These results are compared to experimental values,
and--where possible--the results of no-core shell model calculations using the
same input chiral interaction. We find good agreement between the
equations-of-motion and valence space approaches. Magnetic dipole observables
are generally in reasonable agreement with experiment, while the more
collective electric quadrupole and octupole observables are significantly
underpredicted, often by over an order of magnitude, indicating missing physics
at the present level of truncation.
