Hi!
The emojis you are seeing aren't strictly "from Teams." Teams and Windows 11 now share the same emoji style. Microsoft is adopting this style as the standard, and it is applied during updates. Therefore, the change likely occurred following a recent Windows update rather than due to a specific setting.
There is no way to revert this.
NOTE: An emoji's appearance depends on where it is displayed. An emoji is simply a character, and each application or website renders it using its own style. For example, the same 😀 character entered using the Windows + Period (.) shortcut might look different in another app, document, website, or device.