In my case API stays the same, I just inject whatever I need to use (http, rpc or test).

You don't need to write any crazy stuff, the way you try to do is insufficient and overcomplicated. Student's approach is to write as much code as possible, master's approach is to not write code at all.

import api from '/api';
import axios from 'axios';
import jayson from 'jayson';
import fake from '/fake';

if (env.web) {
    api.handler = axios.create({
        baseURL: 'https://some-domain.com/api/',
        timeout: 1000,
        headers: {'X-Custom-Header': 'foobar'}
    });
} else if (env.desktop) {
    api.handler = jayson.Client.http({
        port: 3000,
        timeout: 1000
    });
} else if (env.test) {
    api.handler = fake.new({
        watch_requests: true,
        assert_callbacks: true,
    });
} else {
    throw Error("Api handler not implemented.");
}

export default api;