I think that the south would have been pretty cool to an England allience after they sided with Lincoln in the 1863 Treaty to end the slave trade on the High Seas, (Yale Law library). That was the political move that caused England to cease it support of the Confederacy.
France, on the other hand, would have been a more likely partner after 1863, because of their refusal to close their border between Mexico and Texas where arms could be shipped to the south by the way of Matamoro. That was why Grant had to take Vicksburg and close the Mississippi River. That was also the reason that Lincoln tryed to overthrow the Maximillian government, in 1864, by getting old one legged General Santa Anna, of Alamo infamy, to leave exile in Cuba and lead a rebellion against Maximillian.
This would have probably lead to the South entering WW I earlier than the United States, because of this friendship with France.
England would have become friends with the South after the war. But probably not before the slaves were given manumission, since it was England and NOT Lincoln who was the most interested in ending the slave trade on the high sea.
Remember that the Confederate Constitution prohibited the importation of slaves into the Confederacy from all countries except one, The UNITED STATES of AMERICA. So unless the Northern states passed the 13th Amendment, after the South won it Independence. There still would have been a slave trade in the North. Remember that the reason why the 13th Amendment passed in the first place was because of the puppet governments of the occupied southern states.
Without the 13th amendment it would have still been legal in the 4 states that were slave states, Missouri, Kentucky, Maryland and Delaware, that remained or were forced to remain in the Union. Plus the Northern traders would have still wanted to supply the market in the south until slavery became uneconomical. The south would have freed it slaves. But it would have been along the lines of the English pattern of manumission, and not by sudden emancipation. But the blacks in the south would have been more intergrated into the Southern economy than they became.