Units

[Aegis]

I just added musketeers to English and it's working fine (using the Venice textures and sprites since they were the closest to England's natural colors). You'll need to modify battle_models.modeldb to define a texture (make a backup of the original first!):

10 musketeers 1 4 54 unit_models/_Units/RN_Light_Lmail/musketeers_lod0.mesh 121 54 unit_models/_Units/RN_Light_Lmail/musketeers_lod1.mesh 900 54 unit_models/_Units/RN_Light_Lmail/musketeers_lod2.mesh 2500 54 unit_models/_Units/RN_Light_Lmail/musketeers_lod3.mesh 6400 5 5 spain 71 unit_models/_Units/RN_Light_Lmail/textures/RN_Light_Lmail_spain.texture 72 unit_models/_Units/RN_Light_Lmail/textures/RN_Light_Lmail_normal.texture 40 unit_sprites/spain_Musketeers_sprite.spr 8 portugal 74 unit_models/_Units/RN_Light_Lmail/textures/RN_Light_Lmail_portugal.texture 72 unit_models/_Units/RN_Light_Lmail/textures/RN_Light_Lmail_normal.texture 43 unit_sprites/portugal_Musketeers_sprite.spr 5 milan 71 unit_models/_Units/RN_Light_Lmail/textures/RN_Light_Lmail_milan.texture 72 unit_models/_Units/RN_Light_Lmail/textures/RN_Light_Lmail_normal.texture 40 unit_sprites/milan_Musketeers_sprite.spr 6 venice 72 unit_models/_Units/RN_Light_Lmail/textures/RN_Light_Lmail_venice.texture 72 unit_models/_Units/RN_Light_Lmail/textures/RN_Light_Lmail_normal.texture 41 unit_sprites/venice_Musketeers_sprite.spr 7 england 72 unit_models/_Units/RN_Light_Lmail/textures/RN_Light_Lmail_venice.texture 72 unit_models/_Units/RN_Light_Lmail/textures/RN_Light_Lmail_normal.texture 41 unit_sprites/venice_Musketeers_sprite.spr 5 5 spain 67 unit_models/AttachmentSets/Final European CB Gun_spain_diff.texture 67 unit_models/AttachmentSets/Final European CB Gun_spain_norm.texture 0  8 portugal 70 unit_models/AttachmentSets/Final European CB Gun_portugal_diff.texture 70 unit_models/AttachmentSets/Final European CB Gun_portugal_norm.texture 0  5 milan 67 unit_models/AttachmentSets/Final European CB Gun_milan_diff.texture 67 unit_models/AttachmentSets/Final European CB Gun_milan_norm.texture 0  6 venice 68 unit_models/AttachmentSets/Final European CB Gun_venice_diff.texture 68 unit_models/AttachmentSets/Final European CB Gun_venice_norm.texture 0  7 england 68 unit_models/AttachmentSets/Final European CB Gun_venice_diff.texture 68 unit_models/AttachmentSets/Final European CB Gun_venice_norm.texture 0  1 4 None 16 MTW2_Fast_Musket 20 MTW2_Non_Shield_Fast 1 19 MTW2_Musket_Primary 1 18 MTW2_Sword_Primary 16 -0.090000004 0 0 -0.34999999 0.80000001 0.60000002 14 musketeers_ug1 1 4 58 unit_models/_Units/RN_Light_Lmail/musketeers_ug1_lod0.mesh 121 58 unit_models/_Units/RN_Light_Lmail/musketeers_ug1_lod1.mesh 900 58 unit_models/_Units/RN_Light_Lmail/musketeers_ug1_lod2.mesh 2500 58 unit_models/_Units/RN_Light_Lmail/musketeers_ug1_lod3.mesh 6400 5 5 spain 71 unit_models/_Units/RN_Light_Lmail/textures/RN_Light_Lmail_spain.texture 72 unit_models/_Units/RN_Light_Lmail/textures/RN_Light_Lmail_normal.texture 44 unit_sprites/spain_Musketeers_ug1_sprite.spr 8 portugal 74 unit_models/_Units/RN_Light_Lmail/textures/RN_Light_Lmail_portugal.texture 72 unit_models/_Units/RN_Light_Lmail/textures/RN_Light_Lmail_normal.texture 47 unit_sprites/portugal_Musketeers_ug1_sprite.spr 5 milan 71 unit_models/_Units/RN_Light_Lmail/textures/RN_Light_Lmail_milan.texture 72 unit_models/_Units/RN_Light_Lmail/textures/RN_Light_Lmail_normal.texture 44 unit_sprites/milan_Musketeers_ug1_sprite.spr 6 venice 72 unit_models/_Units/RN_Light_Lmail/textures/RN_Light_Lmail_venice.texture 72 unit_models/_Units/RN_Light_Lmail/textures/RN_Light_Lmail_normal.texture 45 unit_sprites/venice_Musketeers_ug1_sprite.spr 7 england 72 unit_models/_Units/RN_Light_Lmail/textures/RN_Light_Lmail_venice.texture 72 unit_models/_Units/RN_Light_Lmail/textures/RN_Light_Lmail_normal.texture 45 unit_sprites/venice_Musketeers_ug1_sprite.spr 5 5 spain 67 unit_models/AttachmentSets/Final European CB Gun_spain_diff.texture 67 unit_models/AttachmentSets/Final European CB Gun_spain_norm.texture 0  8 portugal 70 unit_models/AttachmentSets/Final European CB Gun_portugal_diff.texture 70 unit_models/AttachmentSets/Final European CB Gun_portugal_norm.texture 0  5 milan 67 unit_models/AttachmentSets/Final European CB Gun_milan_diff.texture 67 unit_models/AttachmentSets/Final European CB Gun_milan_norm.texture 0  6 venice 68 unit_models/AttachmentSets/Final European CB Gun_venice_diff.texture 68 unit_models/AttachmentSets/Final European CB Gun_venice_norm.texture 0  7 england 68 unit_models/AttachmentSets/Final European CB Gun_venice_diff.texture 68 unit_models/AttachmentSets/Final European CB Gun_venice_norm.texture 0  1 4 None 16 MTW2_Fast_Musket 20 MTW2_Non_Shield_Fast 1 19 MTW2_Musket_Primary 1 18 MTW2_Sword_Primary 16 -0.090000004 0 0 -0.34999999 0.80000001 0.60000002

Find the musketeer entry (open in wordpad, search for " musketeer"), mark all the text, all the way down to "17 trebizond_archers..." (don't include the space before 17), then replace it with the entry above. That'll define textures and sprites (those of Venice) for use by the English, for the standard musketeer model and their upgraded armor model.