Hi Jeongeun Kim,
Currently it is not possible to connect your local/hosted ThingWorx with the PTC hosted ThingWorx Experience Server.
This feature is available for those users who host their own Experience server and the ThingWorx and connect them to each other.
On-premise Experience Server option is available for commercial users.
As per my understanding you can consider connecting ThingWorx (for Experience server) with your local ThingWorx.
Configuring the federation between your local Thingworx and (ES) ThingWorx platform should be one of the possible workaround.