*looks further down the page sarcastically* Yeah I have dusk. Still can't help you with online. I don't play anything online.
Tips for Dusk....
-You can stack 1 digimon ability with 1 accessory item of similar effect, but adding more of either is worthless. For example if you have a Digimon with XP 1 and an XP Ring 1 those two things will stack. If you have 5 XP ring 1's only the first will count. If you have 5 digimon with XP 1 only the first will count.
-Digimon or items with xp, money, or item drop boosting effects can be in the Relief Digimon field. They don't have to be one of the 3 active digimon.
I started making a list of all the digimon that give you XP/Money/Item Drop boosting effects and I can give you some of the better ones if you want.. I recently started a new game on my dusk but I stalled out and didnt get around to finishing my research so my list is incomplete.
I know whatever digimon turns into Darugamon is awesome. From its Rookie form to its Mega form it has XP ability. But I think he stops at Lv4 and there is 5 levels.