In order to avoid the problem, Germany would probably not allow Netanyahu to visit the country in the first place.
If I remember correctly, a former president of the USA cancelled a visit to Switzerland because they were wanted for war crimes. Would Switzerland have arrested that former president of the USA? Hard to say: cancelling the visit was an easier solution for the people who made the decision.
In Britain, an Israeli general arrived by plane but never disembarked because of an outstanding warrant for war crimes. Would they really have arrested the Israeli general? Hard to say: not letting them disembark was an easier solution for the people who made the decision.
If I remember correctly, a former president of the USA cancelled a visit to Switzerland because they were wanted for war crimes. Would Switzerland have arrested that former president of the USA? Hard to say: cancelling the visit was an easier solution for the people who made the decision.
In Britain, an Israeli general arrived by plane but never disembarked because of an outstanding warrant for war crimes. Would they really have arrested the Israeli general? Hard to say: not letting them disembark was an easier solution for the people who made the decision.