Yes, TotalBoat Traditional 5:1 Marine Epoxy can be used to restore wood. It can be used to fill thin cracks and shallow voids. However, it will not effectively penetrate rotten wood.

For soft or rotten wood wood repairs, use TotalBoat Penetrating Epoxy Sealer.

For larger voids, use TotalBoat FixWood Wood Repair Epoxy Putty. 

Also check out the TotalBoat Wood Restoration Kit.