I mean, even then, Warriors offered a diverse enough array of fighting styles for a hypothetical first entry Fire Emblem fighting game. Looking at movesets alone...
Sword Cavalry (Xander)
Axe Cavalry (Frederick)
Archers (Takumi/Sakura/Niles/Anna)
Pegasus Knights (Caeda/Cordelia/Hinoka)
Wyvern Riders/Dracoknights (Minerva/Camilla)
Two styles of Myrmidons (Owain/Ryoma and Navarre/Lyn)
Two styles of infantry Lancers (Oboro for a Naginata style and Azura as a water bending Lance dancer)
Reverse-Grip Sword Dancer (Olivia)
Infantry Axe user (Lissa)
Mage Cavalry (Leo/Elise)
General Magic/Dark Magic Mages (Robin/Tharja)
Light Mage (Linde)
Manakete (Tiki)
Graceful Fencing-styled Lord (Marth/Celica)
Aggressive Charge-In-Head-First Lord (Chrom/Lucina)
Token Basic Style Characters (Rowan/Lianna)
Corrin
That's about nineteen unique movesets to take inspiration from. The only major archetypes missing, really, are Lance Cavalry, Bow Knights, Knights, and Thieves (and Clerics, but they're treated differently within Warriors and are still technically there).
For the purposes of a fighting game, the cast is still very diverse as far as fighting styles go.