Update: 

HomeKit is not a hardware, but a feature or service that allows you to control smart home products using Home App in your Apple devices or use Siri voice command. 

You can set up kasa HomeKit compatible device in an Android or iOS mobile device without other hardware. 

For Homekit models like KP125 & EP25, the whole setup process is done in the Kasa APP, not Home APP or other apps. 

Setup for Apple HomeKit Enabled Kasa Devices - EP25, KP125

• Please make sure you selected the correct model which is Homekit Smart Plug instead of other kasa plug model in set up process, or ios device may force open Home APP when your device is connected to Smart Plug Wi-Fi SSID. 

So far there is a step of scanning the HomekitQR code on Homekit smart plug in the setup, after finishing the setup process, kasa device will show up in Kasa app and you can control device in Kasa APP. 

How to set up your HomeKit-supported Kasa

Here is troubleshooting guide that may help if  you met any error message in the setup process

HomeKit setup troubleshooting

Hello   @Skymax

sorry for the delayed reply,  the whole setup process is done in the kasa APP, not Home app or other app is required if you've selected the model. 

It's regret to know you've returned the unit. I added some information that might help with plug installation in my reply above. 

@GN_2020@Skymax we've shared some improvement suggestion with our team, as far as know there will be option to quit the homekit setup and go through Wifi onboarding, this feature could be released around Aug-Sept.