Le Pen used to be more like Trump before the party got rebranded while Zemour to me comes across as a more rational/restrained individual.
More Michael than Sonny (yes, that is a Godfather reference). And we all know who the Fredo is
Zemour and Trump are "similar" in the sense that none of them are politicians and/or have worked in politics before running for the presidency.
The big difference is that Zemour has been very vocal and implicated in politics, writing books, hosting and guesting TV shows dealing with politics. That kind of thing.
Trump never had that stance and/or played that kind of game. Yes, he gave his opinion on political matters but nothing really out of the public norm.
Iirc, the farthest he, Trump that is, went in "political life" was when he got called (or maybe he wasn't called, I can't remember) to testify before Congress back in 1996 (or 1994) on matters related to real-estate economics and how the US market was being handled. And that was pretty much it, him giving his opinion, or sharing his view, as some sort of expert on the subject (since his fortune is partly/mostly made in that particular field).
So, at least he went in with a certain (and rather substantial) level of experience and insight.
Zemour on the other hand?
Well... he has ideas and opinions? Good for him, but it is just like anybody on Earth.