Between Marine Le Pen and Geert Wilders they can still do a lot of damage to those countries but NL without the EU is a joke and France has way too much to lose (more than the UK did) so I highly doubt (hope?) that this will not come to pass.
Le Pen has less elected member of parliament than I have fingers on one of my hands (and I have the regular five fingers by hand).
Even in their "great swipe" of 2014, they got 14 mayors total. In a country counting roughly 36 000 mayors (yes, I know ...).
The FN is actually very very weak, it keeps being seen doing huge jump forwards in numbers but that's mostly because the others are being very dumb and for the FN a single new member of parliament is a 50% jump ahead, which makes for a good headline.
The FN biggest strength is actually the media attention they get and how it drives them forward, there was a study about that showing they were te party being given the most media attention and it giving them the biggest result boost (despite "we are ignored by the media" being on their main card, like all populist parties)