Add Home Assistant and then use the HE to HA integration to share HE virtual switches to HA. Set each virtual switch to turn OFF in 500ms (or 1 sec if you like).
Pair the buttons to HA and create automations in HA that will turn ON the HE virtual switches when the button is pressed. The you can use the HE virtual switches in automations on HE. You can also share devices directly such as a lights joined to HE and have the buttons toggle the light via button presses on IKEA (or other incompatible with HE buttons) that are paired with HA.
This will let you use those IKEA buttons and any others that are not compatible or stable with HE. Then, since you would already have HA available, you could also use Home Assistant Device Bridge as well, to pass devices that HE cannot join or are not stable on HE in the other direction, such as Aqara and IKEA sensors, etc. Cloud integrations not supported here, but supported on HA.
It’s a much more flexible solution for unsupported devices.
Later, once you really have confidence in the setup as I have in mine, take @aaiyar’s advice and add Zigbee2MQTT instead of the ZHA integration in Home Assistant. This will let you use an even greater number if Zigbee devices than is possible with the ZHA integration, with even greater control over their settings. With z2m, you can even use Green Energy Zigbee devices. And if you read my post below about the Switchbot local integration, you would be all set to use that too, because you would already have the required MQTT broker running. 
