Big Ol' Switcheroo

Lvl: 4th     Range: 25 ft     Casting Time: 1 Action     Components: S     Duration: Instantaneous 

You extend your dominant hand to point at any two targets of similar size within 25 feet of you that you can see, firing a very dim line of energy between the two of them one of these targets can be yourself. these two targets then switch places magically. this spell immediately fails if either target cannot fit in the other target's space. If either of the targets are a creature, they must succeed on a wisdom saving throw against being swapped. A creature can choose to fail this wisdom saving throw if they so choose. 

At Higher Levels: For every level that this is cast above 4th, the range increases by 15 feet. 

Available for Classes: Wizard

If one person fails and one succeeds, did the one with with failed save just teleport to the other one? If not, 4th level spell slot that requires 2 different saves to be useful sounds a bit weird. Does sound really fun though. Like dropping a chicken with a fire immunity stone into lava than casting it on people.

• First line should specify creature or object, "any two targets" doesn't fit with how 5e spells are described.
• 25 feet is a weird distance. 30 or 60 would be more appropriate.
• As mentioned, two saves isn't a great mechanic because if either succeeds nothing works.
• Wisdom isn't the "resist being teleported" stat. It's CON (like Vortex Warp) or maybe CHA.
• This feels like a level 3 spell as written, looking at other teleport spells like Vortex Warp and Dimension Door.

Easiest thing to do would be to require at least one target to be willing (or an object) and only the unwilling target makes the save. This plus 30 foot distance and CON save would put it at 3rd level IMO.