Here is a small Python script which should do what you want. Don't worry if you're not familiar with the Python console, just open it with ctrl+alt+P
or click the
button in the plugins toolbar.
Open a new editor with the notepad icon, paste in the code, change the group names to match yours and click the green arrow to run the code. (see buttons highlighted in image below).

source_group_name = 'Your source group name' #Change to match your group
dest_group_name = 'Your destination group name' #Change to match your group
project = QgsProject().instance()
source_group = project.layerTreeRoot().findGroup(source_group_name)
dest_group = project.layerTreeRoot().findGroup(dest_group_name)
for ltl in source_group.findLayers():
source_style = QgsMapLayerStyle()
source_style.readFromLayer(ltl.layer())
dest_layer = [l.layer() for l in dest_group.findLayers() if l.layer().name()==ltl.layer().name()]
if dest_layer:
source_style.writeToLayer(dest_layer[0])
dest_layer.triggerRepaint()