How to beat steam tanks ?

So I'm doing paint the map with high elves. I'm not very good at this game so my tactic every fight is turtle with 6 melee units + 8 - 10 sisters of averlon and have 2 cav units or my lord on a dragon get the artillery and ranged units in the back. I was getting bored thzt it took so long so started also attacking allies and just everyone that comes in my path to make it quicker. I attacked sigmar and was in war with all dwarfs due to end game crisis. Few turns later I'm in war with every good faction and bad faction of the game. This made the game more fun because it was getting more difficult and needed more tactic instead of steamrolling everyone with autoreslove. Now the big problem... fighting empire , sigmar and other men factions is extremely difficult for me. They have big armies with like mulitple steam tanks , pirate boats , artillery etc. I tried to push forward but they also running cav so my archers and getting caught. And even if they don't get caught. My sisters of averlon are not doing very good against those steam tanks. The pirate ships are easy they get melted but steam tanks take very long to kill even with all of them focusing one. What unit should I use or what tactic should I use against those armies ? Sometimes the dwarves are also hard because they have better ranged and artillery units. But they are easier to kill or disturb then those steam tanks.