Most english texts use an english translation, but make sure they put "droit de suite" in parenthesis. I also found a government text which uses "droit de suite" exclusively. I therefore think that the best way to handle it is to use the French term and use a translation in parenthesis (or vice-versa) the first time you use it, and subsequently use the French expression by itself.

"THE UK Government has publicly
condemned the Artists Resale Levy (Droit
de Suite) proposals this week, promising
to argue "robustly" against their enforced
adoption in the UK by Brussels."

But the same article then goes on using the French term by itself:

(...)Mr Browne said that although it didn't change anything,
Mr McCartney's statement re-emphasised the
Government's determination to fight the Droit de Suite
proposals.
http://www.atg-online.com/news/news17-1.html

"DROIT DE SUITE - ARTIST'S RESALE RIGHT
(...) But also most other European Member States allow
an artist and his beneficiaries after death to share in the profits on subsequent resales of their artwork - the so called "Droit de Suite".
http://www.harbottle.co.uk/pubs/sept96.htm

"4.13 Apart from being expressly recognised in the treaties described above, distribution rights are also recognised in arts. 14ter
and 16 of the Berne Convention. Article 14ter contains an optional provision concerning the droit de suite (or right of subsequent disposal) in respect of original works of art and manuscripts of written works, and art. 16 provides for the seizure of infringing copies of works."
http://law.gov.au/clrc/gen_info/clrc/Report Part 2/chapter4....

"Lord McIntosh of Haringey: My Lords, the noble Lord asks questions about both VAT and droit de suite.
(...) In relation to droit de suite, the evidence is rather confusing.
It appears that in France, where droit de suite has been going since 1920, around 80 per cent. of the receipts go to 20 per
cent. of artists or their families.
(...)Lord Jenkins of Putney: My Lords, is my noble friend the Minister aware that a distinction must be drawn between tax
harmonisation and droit de suite? Is it not the case that tax harmonisation is for the benefit, or otherwise, of governments,
whereas droit de suite is the for the benefit of the artists? Therefore, to draw the two together and put them into a single sack is
quite wrong. "
http://www.parliament.the-stationery-office.co.uk/pa/ld19969...