I just got Emilio, but I already had Ludwig. Ludwig isn’t great on defense, but holds his own. He is okay in rush offenses, but not as good as people think in my opinion because at VF, heroes gain mana fast without him, but the taunt is great. At the same time, be prepared to bring mother north as his sidekick in VF as his taunt usually makes him die quickly and he is vulnerable to DD.
He is good in normal offense if you can help him with mana. Pairing him on a team with Toxicandra, Milena and Xnolphod and a bard all help him to charge hopefully before him or a neighbor dies.
Emilio is fairly straightforward, a healing ailment blocker that has good stats and VF. I just picked him up in SE just for his blocking ability as I don’t have another hero that does that reliably (haven’t ascended my cRumplestilskin yet but he only has a 33% chance to block ailments).
Ludwig shines most in missions, quests and other maps where he can prevent needing to save up specials for the last fight. Even after the nerf, Xnolphod, Ludwig, Alfrike as neighbors are really powerful