I haven't really got many tips for following SW in France, however, if you like Pastis/Pernod, I do recommend you try the alcohol free version. The one I buy is from Leclerc, but all supermarkets do their own. It's in the section with the non-alcoholic cocktail mixes, which is usually next to the spirits. The one I buy is called Pastanis and it's a cloudy yellow colour and labelled sugar free too.
I love this, as it gives the "feel" of real Pastis, in that it numbs your tongue like the real thing and you can only really sip at it. I mix it with sugar-free cordial, which is just becoming available here and class it as syn free!
I also buy alcohol free beer, which is lower in syns and I can't really tell the difference any more. It's not that I don't like alcohol, I love my red wine
I've just throught of something you might like to try. Poulain make a low fat instant hot chocolate drink. Just add hot water, like Options. 40 cals per cup (11g of powder) - so 2 syns - and IMO much nicer than Options. It comes in a curvy hourglass shaped container like the UK brands or in sachets. You'll find it with all the hot chocs in the tea/coffee aisle.
I found a huge selection of 0% fat activia yogurts in Carrefour at the weekend, including my favourite rhubarb flavour. I think the Taillefine 0% fat yogurts are free also - they appear to be available in most of the supermarkets.
The secret is to find yoghurts etc. that are no added sugar and are also fat free (0% sucres ajoutés, 0% matière grasse). You can find lots of things such as flavoured fromage frais that is 0% fat, but has sugar, which need to be synned. Lidl's fat free yoghurts are one such example.
I buy 0% sugar free in the Sveltesse, Activia, Taillefine and Le Panier de Yoplait ranges and every supermarket does its own (cheaper) versions.
There are also some reduced fat cheeses available (Emmental, Brie etc.) as well as some completely fat free quark-style soft cheeses that come in little cubes. They are usually stocked together in a low fat section of the cheese fridge.
Feta is readily available and I have on occasion seen a lower fat one. Lidl do a reduced fat mozzarella as well as a full fat one.
I contacted the manufacturers a couple of years ago. Quorn was tried on the French market a few years back, and it didn't sell well. I am vegetarian and follow SW when I need to lose a couple of kilos. It always works for me, although I should know better than to let the grams creep on. I like and need Quorn for my prolonged stay in Creuse.
I have bought two deluxe boxes from my local JB Packaging in Brixham, they supply boxes to the fish and frozen food industry and with some chill packs in the box, chilled or frozen should stay cold or frozen as long as the box isn't open. They are very helpful.
I intend to try chilled only this spring, and will see how it works, freezing anything which seems to still be chilled enough on arrival after about 36 hours in the boot, when the air temperature should be low. A thermometer in the box should complete the experiment. I can also fit one of their 1.5 kilo boxes in my carry on luggage when I take a short trip across, and airport security assure me there will be no problems with a poly box inside my luggage.
I would rather do all this, as it's my own responsibility and I know how long it has been stored in the chill box and if anything untoward happened. It will be worth it if it works. Sounds complex, but really it's not. On verra.
Another top tip for Frenchies. Leclerc does own brand (Marque Repère) aerosol spray oils, either olive or sunflower. I have used these throughout my weightloss as an alternative to Frylight and have treated them as syn free. I reached target doing this, so it can't have made too much difference!