Newer versions can, but version HKV1.2 and older can not, the KNX bus provides around 320mA over 30V (less than 10 W) which is not sufficient to power both your KNX system and a Thinka.
Doing so can result in your KNX installation becoming irresponsive due to lack of power.
Use a separate KNX power supply, or use the power supply provided by Thinka.
See also powering the Thinka KNX