The bike would certainly feel different if the 65mm suspension fork were to be replaced with a low fitted racing fork. But a slightly higher fork such as a cylclocross or touring fork will be very close to what the suspension fork would be when the rider's weight is slightly compressing it during normal riding.

Medusa, if you're planning on an electric hub you'll want a more skookum front fork anyhow to better avoid flexing the legs due to the driving and braking forces. So a heavy duty cyclocross or touring fork or even a slightly heavier duty rigid 29'er fork would be ideal for your application. But again just watch that the fork is no longer than your old one than by maybe 10 to 15 mm's and that it's no shorter than about 20 to 30 mm than your current crown to axle length. The difference here being the allowance for the static sag that would occur when you're in the saddle. And if you can keep the difference closer than these maximums you'll ensure that your bike handling is less affected by the change.