Are they compatible?

The Banker's Guild and Spells Expander plugs both modify Fantrima. Does this mean they are not compatible, and shouldn't be used together? Or does it not work like that?

Many plugins alter Fantrima. There is no known conflict with them. You can have them all loaded at once. The only conflict I've found is between UberGaurdian and Damsels in Distress. If you have both of those loaded in the end game, the game will crash because each tries to send the player to a different location from the same spot.