Pat fillets dry; score skin several times. Salt and pepper, then pat with Wondra.
Heat oil in a large skillet over medium-high. When oil shimmers and wisps of smoke rise from skillet, add fish in a single layer, skin-sides down. Reduce heat to medium; cook, undisturbed, until skin is crisp and flesh is opaque halfway up sides and almost cooked through, 5 to 7 minutes, depending on thickness.
Flip and continue cooking until just cooked through, 1 to 2 minutes more. Transfer to plates, skin-sides up. Add vermouth to skillet; boil until mostly evaporated, 1 to 2 minutes. Add capers and butter; cook until butter simmers and sauce thickens slightly, about 2 minutes. Remove from heat; stir in herbs. Return fish to skillet, skin-side up; spoon butter sauce over top. Serve immediately.