From UK to France the sheep either need to ;
1) come from a scrapie monitored & MV accredited flock
or
2) Be scrapie genotype ARR/ARR and have 2 tests for MV 6 months apart
Also have to be tested for Brucella Ovis and get the appropriate forms completed by DEFRA & be vet inspected
Transport has to be by an approved vehicle/driver
http://www.defra.gov.uk/animal-trade/exports-non-eu/I've done it often enough over the years and it is a lot of work for the seller , so I double the price of stock being sold and make sure the buyer pays all other costs
If you want fresh blood it would be cheaper to buy what you can in France and then import semen