Worth checking that the Lyngsat listings on 5W are DTH feeds and not DVB-T distribution. If you see Multistream on a Lyngsat listing - it's not aimed at home viewers usually. (Italy and France both have multi stream distribution of their DVB-T networks on 5W AIUI). The FTA DVB-T channels are unencrypted (but 'normal' receivers won't receive them) on these feeds, the pay-TV ones are encrypted.
The France 3 regions in HD on 5°W are for the Fransat platform (DTH). This also carries France 3 Sat in HD though too for some reason.
Then there’s also the version of France 3 Sat on the DVB-T feed multistream transponder (11509H - this is the unencrypted version of France 3 I watch using a PC tuner card which works with multistream). At the transmitter sites, the regional France 3 usually arrives by Microwave/Fibre and gets inserted into the satellite feed transport stream, replacing France 3 Sat. It runs in CBR mode at around 5Mbps to facilitate this (the other France Télévisions channels are stat-muxed in the remaining space). I guess France 3 Sat is carried in the multistream feed as a back-up in case the local feed fails for whatever reason.
Some transmitters that carry two France 3 regions however receive their own dedicated France TV R1 multiplex via fibre/microwave which has all services stat-muxed, including both the France 3s, rather than using the satellite feed at all.
The Fransat HD versions are actually also all ~5Mbps CBR because Fransat offer a “Fransat Pro” service for communal systems/hotels, where you get a set of Fransat CAMs and cards along with a DVB-S2 to DVB-T transmodulator system that decrypts the Fransat channels and modulates them to terrestrial. The system allows the regional France 3 version to be slotted in in the same way as happens terrestrially (Fransat gets the same multiplexed versions of the channels as the terrestrial network, but adds its own EPG
(now and next only) and encryption).