It will be a pretty disappointing experience, in my opinion. Minor Illusion just creates an illusory cat that lures NPCs to a specific area, which is pretty useful if you use it before combat/while stealing, but isn't as versatile as it is in 5e. Disguise Self can be pretty useful for dialogue checks and exploration, but is still pretty limited when compared to 5e. A lot of other notable 5e illusion spells aren't present in the game and the most that were are severely nerfed (Phantasmal Force, Mirror Image, Greater Invisibility).