So, can we count on Louis being smart and avoiding antagonizing the Maritime Powers? Instead he could direct his campaigns against Habsburgs' Italian possessions and Austria. But it wouldn't be the first time he tries to take more than he really can and once he becomes too threatening an alliance is bound to be cobbled up against him.
As for the Southern Netherlands I'm not so sure the Spanish or Vienna would allow it to be handed over to Bavaria and least of all Savoy. If the French move against the Netherlands the Dutch and British will definitely join the war. Louis could possibly get some territories along the border and Luxembourg at most (like he did in 1684) but he should direct his campaign to Italy if he wants to avoid British involvement while being able to easily defeat the the Austrians
Louis will avoid too much antagonization as he focuses his efforts on the Austrians.
The Spanish Netherlands would probably have to forcibly taken. Of course, a French invasion would spark concern in the Netherlands and in England. However, the Bavarians alone could not take the Southern Netherlands. Perhaps, Louis can convince the Dutch to hand it over to the Bavarians, the Dutch did indeed trust Max Emanuel (William, in fact, is responsible for Max's appointment to Governor of the Spanish Netherlands). Or Louis's invasion of the Spanish Netherlands could be accompanied by an explicit proclamation that the invasion was in the interests of the claims of Max Emanuel.