I'm not entirely sure if the X6Play (2nd gen) (42.40mm, 4G) is specifically compatible with Galaxus Mobile. The available information shows that the watch works with nano SIM cards and common network operators, but I do not have explicit confirmation for Galaxus Mobile. I recommend you to consult our Community forum or contact Xplora customer support directly to get a reliable answer.
Am also looking for a smartwatch for my son and the question I ask myself with each of these watches is whether it works with Galaxus Mobile. Am a bit surprised that Galaxus themselves can't definitively say if it is compatible with their own mobile plan.... Would appreciate a reliable answer before I order the watch and then have to send it back....