Note: the proposed change is TWF fighting style and dual wielder feats each adding an extra bonus action attack as your Extra Attack feature gets upgraded to a maximum of 3 for fighters and 2 for other classes.
Tier 1: Level 2 Fighters, no feats, appropriate fighting styles, 20 in primary offense attribute, Action Surge applied after /
Great Sword
+7 to hit, 2d6+5 / +2d6+5
Min: 7 / 14 Avg: 12 / 24 Max: 17 / 34
Archery
+9 to hit, 1d8+5 / +1d8+5
Min: 6 / 12 Avg: 9.5 / 19 Max 13 / 26
Sword & Board
+7 to hit, 1d8+7 / +1d8+7
Min: 8 / 16 Avg 11.5 / 23 Max 15 / 30
Dual Wielder
+7 to hit, 1d6+5 + BA 1d6+5 / +1d6+5
Min: 12 / 18 Avg: 17 / 25.5 Max: 22 / 33
Tier 2: Level 5 Fighters, appropriate fighting style feats applied (sharpshooter/dual wielder/gwm/), action surge applied after /, +1 Weapons
Great Sword
+4 to hit, 4d6+32 / 4d6+32
Min: 36 / 72 Avg: 46 / 92 Max: 56 / 112
Archery
+6 to hit, 2d8+32 / 2d8+32
Min: 34 / 68 Avg: 41 / 82 Max: 48 / 96
Sword & Board
+9 to hit, 2d8+16 / 2d8+16
Min: 18 / 36 Avg: 25 / 50 Max: 32 / 64
Dual Wielder PHB
+9 to hit, 2d8+12 + 1d8+6 / 2d8+12 x2
Min: 21 / 35 Avg: 31.5 / 52.5 Max: 42 / 70
Dual Wielder House Rule
+9 to hit, 2d8+12 + 2d8+12 / + 2d8+12 x2
Min: 28 / 42 Avg: 42 / 63 Max: 56 / 84
Tier 3: Level 11 Fighters, additional feats applied (crossbow expert/polearm mastery) for additional cheese builds, +2 weapons now, action surge, blah blah blah
Great Sword
+6 to hit, 6d6+51 / 6d6+51
Min: 57 / 114 Avg: 72 / 144 Max: 87 / 174
PAM/GWM
+6 to hit, 3d10+51 +1d4+17 / 3d10+51
Min: 72 / 126 Avg: 87 / 154.5 Max: 102 / 183
Archery
+8 to hit, 3d8+51 / 3d8+51
Min: 54 / 108 Avg: 64.5 / 129 Max: 75 / 150
LE EBIN HAND XBOW EXPERT
+8 to hit, 3d4+51 +1d4+12 / 3d4+51
Min: 67 / 121 Avg: 73 / 131.5 Max: 79 / 142
Sword & Board
+11 to hit, 3d8+27 / 3d8+27
Min: 30 / 60 Avg: 40.5 / 81 Max: 51 / 102
Dual Wielder PHB
+11 to hit, 3d8+21 + 1d8+7 / 3d8+21
Min: 32 / 56 Avg: 46 / 80.5 Max: 60 / 105
Dual Wielder House Rule
+11 to hit, 3d8+21 + 3d8+21 / + 3d8+21
Min: 48 / 72 Avg: 69(nice) / 93.5 Max: 90 / 135
Tier 4: Level 20, +3 weapons, feets, surges
Great Sword
+9 to hit, 8d6+72 / 8d6+72
Min: 80 / 160 Avg: 100 / 200 Max: 120 / 240
PAM/GWM
+9 to hit, 4d10+72 +1d4+18 / 4d10+72
Min: 95 / 171 Avg: 114.5 / 184 Max: 134 / 246
Archery
+11 to hit, 4d8+72 / 4d8+72
Min: 76 / 152 Avg: 90 / 180 Max: 108 / 216
The Virgin Hand Crossbow Expert
+11 to hit, 4d4+72 +1d4+18 / 4d4+72
Min: 95 / 171 Avg: 102.5 / 184.5 Max: 110 / 198
The Chad Greatbowman (oversized long bow)
+11 to hit, 8d6+72 / 8d6+72
Min: 80 / 160 Avg: 100 / 200 Max: 120 / 240
Sword & Board
+14 to hit, 4d8+40 / 4d8+40
Min: 44 / 88 Avg: 58 / 116 Max: 72 / 144
Dual Wielder PHB
+14 to hit, 4d8+32 + 1d8+8 / 4d8+32
Min: 45 / 81 Avg: 62.5 / 112.5 Max: 80 / 144
Dual Wielder House Rule
+14 to hit, 4d8+32 + 3d8+24 / + 4d8+32
Min: 63 / 99 Avg: 87.5 / 137.5 Max: 112 / 176