JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/3.0.0-rc/chart.js"></script>
<canvas id="chart"></canvas>

JavaScript

const pointInArea = (point, area) => (
	point.x >= area.left && point.x <= area.right &&
  point.y >= area.top && point.y <= area.bottom
);

Chart.Interaction.modes.labels = (chart, e, options, useFinalPosition) => {
	const position = Chart.helpers.getRelativePosition(e, chart);
	const scale = chart.scales.r;
  const elements = [];
  
  let dataIndex = null;
  
  for (let i = 0 ; i < chart.data.labels.length; ++i) {
		const labelPos = scale.getPointLabelPosition(i);
    if (pointInArea(position, labelPos)) {
    	dataIndex = i;
      break;
    }
	}
  
  if (dataIndex !== null) {
  	for (let i = 0; i < chart.data.datasets.length; ++i) {
    	const meta = chart.getDatasetMeta(i);
      elements.push({
      	element: meta.data[dataIndex],
        datasetIndex: i,
        index: dataIndex,
      });
    }
  }
  
  return elements;
};

const chart = new Chart('chart', {
	type: 'radar',
  data: {
  	datasets: [{
    	data: [10, 20, 30, 40, 5],
      label: 'DS',
    }],
    labels: [
    	'Label 1',
      'Label 2',
      'Label 3',
      'Label 4',
      'Label 5',
    ]
  },
  options: {
  	plugins: {
    	tooltip: {
      	mode: 'labels'
      }
    }
  }
})