Even if it is just Napoleon vs the USA there is n way France could sustain an invading forces in the USA. St Pierre and Miquelon in the north and Haiti and the Caribbean in the south simply cannot be adequate logistical forward bases (assuming Haiti is even under French control). The French Navy and merchant marine are limited, and the USN while small, can with augmentation by privateers, fight a guerre de course making supplying any troops in the USA a nightmare. Unlike during the American Revolution, where the British had a level of support among the local population, the French will be facing a completely hostile population and that population would make the partisan "problem" in Spain look like a walk in the park. The French connections with the Indians have gone away since Queen Anne's War/French and Indian War, so there won't be a second front like the British had going for them during the War of 1812.
All of this assumes Napoleon has gone totally batshit nuts to even try this.