F1 – F4 hybrids banned, F5 and later gen. allowed, but either need to put into a 4 month quarantine or vaccinated at 3 months against rabies, keep the kitten 4 months, do a rabies titer test and then the kitten can be shipped without quarantine.
In order to import to Europe CITES import and export permits are required for F1 – F4 hybrids. From F5 on no CITES is needed, instead a TICA 5 generation pedigree to prove the cat is 5 generations removed from the wild cat. There are different regulations in each country for keeping hybrids.