SwitchForms.js

function switchForm(executionContext) {
    var mainFormId = "cf74c4d2-2696-4298-9166-e53d79a6bd07";
    var alternativeFormId = "cf4fc8f1-08c6-4ae3-9dcf-45a11838a00a";

    //Get formContext.
    var formContext = executionContext.getFormContext();
    //Get all the available forms for the current user.
    var listOfAvailableForms = formContext.ui.formSelector.items.get();
    //ID of the current form.
    var currentFormId = formContext.ui.formSelector.getCurrentItem().getId();

    var myAttribute = formContext.getAttribute("myAttribute").getValue();
    //Checking if user has access to alternative form and the current form isn't the alternative.
    if (myAttribute === 1 && currentFormId !== alternativeFormId) {
        listOfAvailableForms.forEach(element => {
            if (element.getId() === alternativeFormId) {
                element.navigate();
            }
        });
    }
}