If the first officer is considered legally as second in command then presumably he would be certified competent at the end of his type rating to take off and land up to the aircraft limiting crosswind component. After all he has a command type rating - not a co-pilot type rating.
If the airline has a crosswind limitation for copilots, beyond which the captain must land, then clearly the airline does not trust the copilots training to type rating competency. Yet, in event of incapacitation of the captain, the second in command takes charge. Does that now mean he can safely land up to the maximum recommended cross-wind component? Methinks some inconsistency here.
So now lets face the real truth. Either the type rating provider is not training the candidate on enough max component crosswind take off and landings to be safe but nevertheless slyly ticking the required box to keep the syllabus moving along. This is usually a cost aspect involved with extra simulator sessions. That is the most likely scenario.
Or, the candidate simply is unable to consistently demonstrate the skill in the simulator to land in max crosswind components. If that is the case, the instructor could be sorely tempted to tick the box anyway rather than making waves by scrubbing the candidate as unable to reach required skill level. Especially if the candidate is self funding his own type rating.