Roussel appears to be polling at about the same level as the PS candidate (both at an anaemic 3%) which is an improvment on Mari_George Buffet's 2%.

Here is an interview with him. He suggests cancelling COVID-19 related French government debt which is interesting but some of the rest of his comments sound somewhat strange:

"We know how to work with everyone: when we were in de Gaulle’s government when we contributed to Mitterrand’s victory.

We are unifiers and we know how to work with the broadest possible groupings when it is in the service of the nation."

https://www.euractiv.com/section/elections/interview/communist-candidate-in-french-2022-election-we-are-very-different-from-melenchon/