I downloaded it as a 'zip' file from git to install the plugin.
After that, I opened package.json and modified kibana version to 7.6.1.
And the following command was executed by compressing the plugin file back into a zip file.
.\bin\kibana-plugin.bat install file:///D:\ES\kibana-7.6.1-windows-x86_64\kibana_ext_metrics.zip
The error is as follows.
If this plugin can be applied to version 7.6.1, please guide in detail the parts and commands to be modified.(No node.js and react.js experience)