I searched for a possibility to make content multilingual. So I try to use a bb-code to do it and it worked. So I will share to have more testing users and feedback.

If you want to have multilingual content you could create a new bbcode:

-BB Code Tag Name: translate (you should use something that others could not imagine to avoid other users to use it - if necessary)

-Replacement:
HTML-Kodu:
<span class="vb_translation_{option}">{param}</span>
- Example:
HTML-Kodu:
<span class="translation_1">This is a english text</span>
-Use {option}: Yes
-Remove Tag If Empty: Yes
-Disable BB Code Within This BB Code:No
-Disable Smilies Within This BB Code:No
-Disable Word Wrapping Within This BB Code:No
-Disable Automatic Link Parsing Within This BB Code:No

Now you have to create a new template and put in the following:
Templatename: YourTitle

HTML-Kodu:
<style>
.translation_{vb:raw preferred_languageid} {
	display:none;
}
</style>
Save!

We will use a hook to get the css working:

Hook Location: footer_before_body_end
Title: Your title
Template Name: YourTitle

Save!

Thats it! If you change your language the text of language 1 one is not displayed anymore. Instead you will see the text in any other language.

You could use the bbcode in forum, article and every content like this:
[translate=1]This is a english text[/translate]
[translate=2]Das ist ein deutscher Text[/translate]

Pros:
- have more than one language in one post.
- google will crawl both (or more) languages. (not the best way for seo!)

Cons:
- Perhaps you have to increase postmaxchars to post in more than one language.
- You have to define a text for all languages or the post is empty!
- Didn't found any others yet!