Fully custom sprites are coming soon to Adventure Maker
Here's a mod one of the users the discord has made (KOOLKID67890)
This is just to show off that you can use custom tiles now. These are not actual sprites that will be used in game. :P
You can download and support the game here: https://www.patreon.com/DreamMix
You can also join the Discord here: https://discord.gg/B29C2Wa
$10 patrons already have this feature, but I will release a stable version of this feature later this month to $5 patrons.