pokemons-async.js

const showPokemon = pokemon => {
  const body = document.querySelector('body');
  const image = document.createElement('img');
  image.src = pokemon.sprites.front_default;

  body.appendChild(image);
};

const pokemonList = [
  'https://pokeapi.co/api/v2/pokemon/1',
  'https://pokeapi.co/api/v2/pokemon/10',
  'https://pokeapi.co/api/v2/pokemon/12',
  'https://pokeapi.co/api/v2/pokemon/45',
  'https://pokeapi.co/api/v2/pokemon/64',
  'https://pokeapi.co/api/v2/pokemon/78',
  'https://pokeapi.co/api/v2/pokemon/3',
  'https://pokeapi.co/api/v2/pokemon/21',
  'https://pokeapi.co/api/v2/pokemon/26',
  'https://pokeapi.co/api/v2/pokemon/39',
];


const getPokemon = async(pokemonUrl) => fetch(pokemonUrl).then(res => res.json());

(() => {

  const requestsList = [...pokemonList];

  const getNextPokemon = async(requestsList) => {

    if (!requestsList.length) {
      console.log('Done!');
      return;
    }

    const currReqList = requestsList.slice(0, 3);

    const pokemonsToRender = await Promise.all(
      currReqList.map( url => getPokemon(url))
    );

    pokemonsToRender.forEach( pokemon => showPokemon(pokemon));

    const nextReqList = requestsList.slice(3);

    getNextPokemon(nextReqList);
  };

  getNextPokemon(requestsList);

})();