I have serious doubts if France can get its navy back up after Trafalgar. Hell I say Britain will make sure to exert as much naval power as powerful after Napoleon’s victory.
Where will Britain get the money to finance this powerdul navy? Britain's going broke and much poorer than in IOTL. It's been spending wildly while it's economy is shrinker.
Britain's lost a fortune in the continental wars, both paying for its army and financing these wars, with no return on the mone.
Britain's also wasted a fortune in it's Latin American adventures.
Britain's lost much of its army and even more of the army's artillery and other equipment. Re-building and re-equipping the army will cost several fortunes.
Maintaining the Royal Navy's marginally effective blockade is not only costing Britain another fortune, but it's also wearing out the Royal Naval. Plus, the Royal Navy has no allied navies, so its duties have increased.
Further, the Royal Navy is having trouble finding enough men to man its ships--they've been forced to impress more men. This shortage of men only can become worse as the navy will have to compete against the army for men as the army has to rebuild. (And the loss of all the army's artillery in Europe means the army will be competing with RN for material and labor needed to make cannons.)
Beside spending all that money in its foolish wars, Britain's losing major sources of revenue. Britain's lost all its trade in the Baltic, with France, with Iberia, and with much, if not all, the rest of Europe. Britain's also lost much of its trade with Latin America . Plus, its facing more competition in maritime trade, particularly with America. With trade down, goods will be scarce, and prices will rise. Plus, the treasury's revenue will be down, so paying for the RN will be more difficult.
Another smaller thing is that in this time line the RN has suffered more losses than in OTL. These losses are small, but they they are still losses. They affect morale of the RN, lowering--and raising that of the RN's opponents.
With less money, fewer men, more duties, no allies, greater losses, and lower morale, I doubt the Royal Navy in this time line is anywhere near