High-energy gamma rays have been detected in the region of LHAASO~J2108+5157 by the Fermi–LAT, HAWC and LHAASO-KM2A observatories. Cygnus~OB2 in Cygnus–X has been confirmed as the first strong stellar cluster PeVatron in our Galaxy. Thus, the star–forming regions Kronberger~80 and Kronberger~82, located in the field of LHAASO~J2108+5157, are analyzed to evaluate their stellar population and potential as associated PeVatron candidates. A distance of 10~kpc is adopted for Kronberger~80, while 1.6~kpc is estimated for Kronberger~82. Based on stellar densities, we report that their cluster radii are 2.5 and 2.0, while IR photometry reveals poor stellar content in massive O-type stars in both cases. From optical data, the estimation of cluster ages are 5–12.6~Myr and 5~Myr, respectively. We conclude that, in contrast to the stellar content of Cygnus~OB2, it is unlikely that Kronberger~80 and Kronberger~82 are PeVatrons associated with LHAASO~J2108+5157. The presence of a PeVatron in this region remains a mystery, but we confirm that the two Kronberger regions are star–forming regions undergoing formation rather than evolution.

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