There’s a similar question for 3.5e where the answer is ‘unanswered’, but I’m hoping there’s something in 5e that’s different.
To set an example scene: You’re a Draconic Bloodline Sorcerer with Draconic Resilience. You’re also a Bladesinging Wizard, and you’ve activated Bladesong. You have two attuned items. You’ve cast Haste and Invisibility on yourself. The Bard has given you inspiration. You’ve been frightened by an enemy, but you’ve charmed them back. You proceed to use Magic Jar on a random goblin.
What is carried over? What if you did all that as the goblin, then returned to your own body? Do the effects affect the body, or the ‘soul’?