Create a build directory and run
cmake -DCMAKE_PREFIX_PATH=<path_to_qtcreator> -DCMAKE_BUILD_TYPE=RelWithDebInfo <path_to_plugin_source>
cmake --build .
where <path_to_qtcreator> is the relative or absolute path to a Qt Creator build directory, or to a
combined binary and development package (Windows / Linux), or to the Qt Creator.app/Contents/Resources/
directory of a combined binary and development package (macOS), and <path_to_plugin_source> is the
relative or absolute path to this plugin directory.
Run a compatible Qt Creator with the additional command line argument
-pluginpath <path_to_plugin>
where <path_to_plugin> is the path to the resulting plugin library in the build directory
(<plugin_build>/lib/qtcreator/plugins on Windows and Linux,
<plugin_build>/Qt Creator.app/Contents/PlugIns on macOS).
You might want to add -temporarycleansettings (or -tcs) to ensure that the opened Qt Creator
instance cannot mess with your user-global Qt Creator settings.
When building and running the plugin from Qt Creator, you can use
-pluginpath "%{buildDir}/lib/qtcreator/plugins" -tcs
on Windows and Linux, or
-pluginpath "%{buildDir}/Qt Creator.app/Contents/PlugIns" -tcs
for the Command line arguments field in the run settings.