Why converting LCS into corvettes would not fix the fleet gap

Could the Freedom and Independence classes be adapted into adequate corvettes?

Yes, but the Navy lacks enough hulls for the conversion to supply fleet mass and still needs the available ships for mine-warfare missions.

Freedom and Independence could be adapted for a corvette role. The available hulls are few, and the US Navy still needs them for minesweeping and mine-clearance duties. Assigning them to another mission would compete with a role for which few other hulls are available.