Could the alternate German carriers raid Britain's east coast?
Short answerNot usefully against southern Britain, but they might threaten northern Scotland, Iceland, or convoys where opposition and target scale are more favorable.
NotesThe Luftwaffe already sends land-based raids numbering in the hundreds against Britain, making a carrier group of roughly 42 aircraft a poor tool for attacking London or southern targets. Such a raid would also enter the reach of British fighters and radar-supported defenses. Northern Scotland, Iceland, and Atlantic convoys are more plausible objectives. The carrier can reach southern Britain, but its limited air group is better used against maritime or northern targets.