Windows command for elasticsearch :
C:\Users\ABC\Desktop\ELK\elasticsearch-6.2.2\bin>elasticsearch-plugin.bat install file:///C:\Users\ABC\Desktop\ELK\x-pack-6.2.2.zip
Windows command for kibana:
C:\Users\ABC\Desktop\ELK\kibana-6.2.2\kibana-6.2.2-windows-x86_64\bin>kibana-plugin.bat install file:///C:\Users\ABC\Desktop\ELK\x-pack-6.2.2.zip
Windows command for logstash:
C:\Users\ABC\Desktop\ELK\logstash-6.2.2\bin>logstash-plugin.bat install file://C:/Users/ABC/Desktop/ELK/x-pack-6.2.2.zip
*Note: Keep in mind for logstash file path is different