[voraa]

Совсем "по правилам" надо так добавлять
test.js

const methods = {
	function test() {
		console.log(this.name)
	}
} 

module.exports = methods

const methods = require('./test')
 
class Tmp {
     
    constructor(name) {
        //....
    }
    home() {
        //...
    }
}
 methods.__proto__ = Tmp.prototype.__proto__
Object.defineProperty(Tmp.prototype, 'test', {
            writable: true,
            enumerable: false,
            configurable: true,
            value: methods.test,
        });