I sympathize. Many of my recent transplants have suffered frm awful waterlogging; some even blew right out of the ground in the horrific winds that accompanied the last couple of storms.

The roots of your tomatoes & peppers are probably drowning (roots need to "breathe" oxygen from air pockets in well-drained soil) and maybe even rotting. Don't fertilize! That will encourage leaf development, when what you want now is for those roots to dry out and begin growing again. I'd suggest leaving the plants alone until you (hopefully) see signs of recovery and new shoot production.