How to configure @typescript-eslint rules

Using a .eslintrc.js configuration file you have to add this to the "rules" section:

"rules": {
    "@typescript-eslint/member-delimiter-style": ["error", {
      multiline: {
        delimiter: 'none',    // 'none' or 'semi' or 'comma'
        requireLast: true,
      singleline: {
        delimiter: 'semi',    // 'semi' or 'comma'
        requireLast: false,

Worked for me for the "@typescript-eslint/explicit-function-return-type" parameter. Options are from the rules project site on github

Thanks to maxkoryukov for improving my original answer.