The motion is to be put forward by the left-wing New Popular Front party and will be supported by Le Pen's far-right National Rally party. The key number to watch out for is 289 votes out of the 577 parliamentary seats. But given the alliance between the two parties above, it should see that threshold reached.
There will then be calls for Macron to resign surely. However, he has been adamant that he wants to stay on in his post as president for now. And sadly, incumbent prime minister, Michel Barnier, will have to be the scapegoat. In any case, just be wary of this as it will be a risk for the euro and French assets in the day ahead.