  The satellite Planetary Transits and Oscillations of stars (PLATO), due to be
launched late 2026, will provide us with an unprecedented sample of light
curves of solar-type stars that will exhibit both solar-type oscillations and
signatures of activity-induced brightness modulations. Solar-type pulsators
only have moderate levels of activity because high levels of activity inhibit
oscillations. This means that these targets represent a specific challenge for
starspot modelling. In order to assess the possibilities that PLATO will soon
open, we wish to characterise the morphology of active regions at the surface
of stars for which we also have a detection of solar-like acoustic
oscillations. In this context, we report the results of an ensemble starspot
modelling analysis of the Sun and ten solar-type pulsators observed by the
Kepler satellite. We implement a Bayesian starspot modelling approach based on
a continuous-grid model, accounting for the combined starspot and facular
contribution to activity-induced brightness modulations. From our analysis, we
find that several stars of our sample exhibit clear signatures of stable
longitudinal active nests while sharing activity levels and convection versus
rotation regimes similar to the solar regime. By searching for modulations in
the reconstructed starspot coverage, we found significant periodicities that we
identify as possible signatures of cyclic modulations similar to the
quasi-biennal oscillation or the Rieger cycle. We can infer the corresponding
intensity of the magnetic field at the bottom of the convective envelope based
on the hypothesis that internal magneto-Rossby waves acting on the tachocline
cause these modulations.
