I wouldn't hate it...
One element the Pacers need more of in their roster is strong shooting, and Kispert could use a change of scenery.
This effectively flips two end of bench guys for Indy into a second-unit 3-point shooting wing who contributes. It's difficult to say Walker and Furphy can contribute with Carlisle's rotations and their usage.
For Walker, this is also a great change of scenery. The Wizards are lacking at the PF spot, Walker's natural position. It's been awkward and probably annoying for Walker to be pushed by Indy to play at SF. Developing a player shouldn't involve clearly playing him at a position that doesn't fit.
It'll be difficult for Washington to find any assets better than Walker for Kispert in their rebuild, so it's worth grabbing him and lowering their payroll at the same time.
Pacers love acquiring role guys on good, long-term contracts who have yet to hit their ceiling.