EDIT: Yes it is possible and works flawlessly. My suggestion: Build everything in de default language, then activate Polylang, then start translating. Worked for me like a charm. Another hint: Metabox is best to use with Polylang. With ACF you need to recreate the fields for every language, as with Metabox you can just simply attach the same fields to the different languages and it works.
Is it possible to start building my website and add/use Polylang later on or will this cause issues?