All of these fantasies are just that, fantasies.
In the first place Jackson lost his arm May 2.
Hood's arm was injured at Gettysburg, not amputated and he did not return to duty until September, nearly two months later.
Otis Howard lost an arm at Fair Oaks on June 1 and didn't return to duty until September three months later.
The odds of Jackson being ready to march north with Lee the first week of June are slim.
Several sources I've read indicate Lee had considered creating a third corps even before Jackson's death.
So even if Jackson survives it's probable he would have commanded only Ewell's II Corps force.
Since Ewell was senior he would probably have been given the III Corps.
Question now becomes does Gettysburg even happen. With these changes the division commands are different.
Finally all this business of England ever supporting the Confederacy is a fantasy.
Once the Emancipation Proclamation was issued and in force it became a war against slavery and England had abolished slavery 30 years earlier and had sent warships to halt the African slave trade.
As much as Napoleon III would have liked to support the Confederacy he would not do so without England going along with him and it's unlikely any government in England could have survived supporting it.
If you would like to see more on the Jackson survival subject try this link.
https://generalmeadesociety.org/research-articles/You'll find a link to a pdf download WOULD STONEWALL HAVE EVEN BEEN THERE? covering this very subject from several angles.