If you connect your kawai cl30 piano to Logic via MIDI, the sounds you will hear from Logic is the sound of the instantiated plugin, likely a sampled piano plugin instrument. That one will most likely sound different from the sound of your kawai cl30.
The delay might be caused by how you set the MIDI on your kawai. Have you tried setting it to Local Off?
LogicPro 10.6.1 ( & 9.1.8),MainStage3.5.1
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