Do you guys know how large was Big mom army? As I remember correctly alone 10000k attacking the Germa66, a another troup with 10000k was in mirrorworld. Also Big mom with Perospero lead a huge large fleet of ships and a huge army, Smoothie/Daifuku aswell.
20000k men power on land, probably 20000-30000k on sea with ships, combinated Big mom probably has a army of 40000-50000 soldiers which is very huge and dangerous.
I mean Kaido has only 20000k withour Orochi troup, but to be fair Big mom controlling more islands. Still the number of Big mom army is insane large, in currently combination they have over 80000 at least.
No wonder why the Navy fear such a alliance between Yonkous.
Big mom has tons of battleships, probably even 1000. And a large huge ships with great fire power. On land and sea Big mom has a great army. Also tons of Ministers,Strong normal pirates(as Tamago), the Veterans and of course Sweet commanders show why no one yet defeat Big mom on her territory. To attack Big mom you would need a huge large army.
Great information which we get in the last chapter.