Best-practice to test if add-on can be used with ember-engines

I’m trying to find some information about how to set-up testing for ember add-on when used in ember-engines. For example, I’m aware that

let i18n = app.__container__.lookup('service:i18n');

will not work in engines but I would like to run a simple (integration?) test whether we don’t have more such issues. Is there any documentation/blog/best-practice (ember-engines do not have testing page ready yet) ?

Thanks

Any reason why it won’t work, I am also facing the same issue when using ember-i18n with engines. What could be the best way to solve this?