What if advisers in the court of Louis XVI reacted to the British troubles in the 13 colonies not by seeing this as an opportunity to humble Britain overseas in a war of revenge but as an opportunity to achieve political-diplomatic objectives in Europe, while Britain is preoccupied with intra-imperial problems and, perhaps, less able to interfere in Europe.
From the British evacuation from Boston and American Declaration of Independence in 1776, the French court investigates several options for political-diplomatic, even territorial gains, especially in Europe, that do not involve directly clashing with Britain.
Finally the War of Bavarian Succession in 1778 provides Paris the opportunity it is waiting for.
https://en.wikipedia.org/wiki/War_of_the_Bavarian_Succession
In response to this Austro-Prussian clash, a France unemcumbered by commitments to the Americans or war preparations against Britain can offer its support to the highest bidder.
Perhaps the simplest approach could be for France to propose support for its Austrian ally against Prussia and Saxony over the Bavarian Succession in exchange for a substantial price, Bourbon control of the Austrian Netherlands. (partially reviving the formula of the 1757 treaty of Versailles
https://en.wikipedia.org/wiki/Treaty_of_Versailles_(1757)).
Remember again, in this ATL, France has neither recognized the Continentals, signed an alliance with them or gone beyond providing some supplies covertly.
Would the Austrians in 1778 be willing to see Austrian Netherlands be transferred to French occupation and Bourbon rule (perhaps under the Duke of Parma, if not Louis XVI himself) in exchange for French diplomatic support on the Bavarian Succession issue, subsidies for the Austrian military effort, and possibly even the participation of French troops against the Prussians?
If the Austrians agreed to such a deal and began implementing it immediately, French garrisons could begin to replace Austrian garrisons in Belgium, freeing up the latter to serve elsewhere in Germany.
How would varying degrees of French intervention in favor of Austria affect the outcome of the Austrian bid for Bavaria, and the general political situation in the HRE?
Would France be able to peacefully occupy of Belgium? Or would Prussians, Dutch or others (including local groups) fight in Belgium to prevent French occupation. If they did resist the French, would they prevail?
What would the Russians do, if anything, in response to this French move in 1778-1779?
What would the British do? Would they decide to not confront France over the move into Belgium, while focusing on pacifying the 13 colonies? Would they shift their focus to Europe and fight the French moves in Belgium while winding down the war with the Americans, perhaps conceding continental independence early? Would the British attempt to both fight to keep the French out of Belgium and to put down the American rebellion at the same time over the next few years?
What would have been the most likely consequences of Britain choosing any of these three courses of action?