Bilingual SEO: Does it work?

[esopezo21]

I am in the process of preparing a squarespace website for my pet accessories brand. I would like to attract traffic from all around the Europe, so I have to translate my website to at least 3-4 languages. (English, German, Italian, French) For the first step, I am thinking to move on just with the german and english versions. As all the keywords, meta descriptions and tags will be translated, I am wondering if it will affect the SEO power? Do you guys gave any prior experience on this? Does bilingual SEO work for both languages?
I came across some sources that state it can lead to slower indexing and negative affect on SEO power.