Left-wing politics support social equality and egalitarianism, often in opposition of social hierarchy. Left-wing politics typically involve a concern for those in society whom its adherents perceive as disadvantaged relative to others as well as a belief that there are unjustified inequalities that need to be reduced or abolished.
Right-wing politics is generally defined by support of the view that certain social orders and hierarchies are inevitable, natural, normal, or desirable, typically supporting this position on the basis of natural law, economics, authority or tradition.
By French tradition dating from the Tennis Court oaths at the beginning of the French Revolution, LEFT is human rights before property rights, RIGHT is property rights before human rights.
If you support the proposition that "all men were created equal" then you are a left winger. If you are loyal to the principle of democracy, then you are a left-winger, by definition. If you are a faithful Christian, then you are a left-winger by definition. No people who respect themselves and their personal autonomy would ever want to be dominated by government and no practitioner of the golden rule would support domination according to social hierarchy since they themselves would not want to be dominated.
Le Pen is an economic nationalist. She's no capitalist. She believes the state should run the machines of industry and intervene in the economy at every level. Le Pen believes that banks should be prevented from investing in markets. She believes investors be should restricted to investing in France. She's against privatization of any govt service. She opposes the admission of Ukraine into NATO and calls for French friendship with Putin's dictatorship. Le Pen would ban the wearing of yarmulkes or other religious outer wear. Le Pen doesn't sound like a friend of liberty to me.
You might call it far-left from the perspective of the far-right, but there were many candidates far left of these two and other candidates far right of these two- more left than right, generally speaking although in France there's nationalist liberal-conservative parties so the spectrum is more diverse than in the US. There's no doubt the French center is far left of the American center, which is all you really saying here. LePen has moved steadily left since 2011 in effort to make herself more palatable but can you trust political changes of mind made only for political gain?
