EDIT
I have deleted my previous answer as spell checking and proofing was not much related to your question. I leave the link for anyone interested in spell-checking the latex with languageTool and OmegaT
http://wiki.languagetool.org/checking-la-tex-with-languagetool
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Your question encouraged me to test how OmegaT can be used for translation with latex projects, below I put my findings:
First of all you need OmegaT, I used version 4.1.1beta. The software can be downloaded from the OmegaT project website as well as from sourceforge . On Windows, I suggest to install it in a dedicated folder, not in Program Files, as you will need to edit some files, e.g., in case you use machine translation like google or Bing
You do not need any plugins for latex. The current version support latex files.
Create a project in OmegaT. A project contains many different files and folders e.g. source (where your source files are placed, target (where the output is stored)
Add all latex files that contain text to be translated to the project. Note that in OmegaT you will be able only to edit the pure test, some math formulas maybe, but the majority of latex markup is not editable during the translation. Also note that the files are copied to the source folder in OmegaT project and I don't believe that these can be updated during the ongoing translation. you can add new files, but you cannot edit files that you started translating.
OmegaT splits the text onto segments and adds special Tags in the text, which allow later to put the text back into the original markup. Segments are sentences or paragraphs, or some other parts depending on the setup
You translate all segments
To produce the output, you run a Create Translated Document command (Ctrl-D). This can be repeated many times. It is needed to see the current result.
The target folder gets populated with the .tex files added to the project bit the text is replaced with the translation.
You copy the rest of important files from your original latex project to the target folders e.g. all figures, .eps files, graphics, etc
Compile the latex project with latex tools inside the target folder of OmegaT project. You should get the new translated version of your latex document
I suggest to search for OmegaT on YouTube - there are plenty of nice tutorials how to use OmegaT. Not with latex but there are no differences, I guess.
Last but not least, I mange to do all the above steps but failed to get the desired result. There is a bug (or I am doing something wrong). The main.tex file which is the main file in my latex project is corrupted - the CR/LF are replaced with LF or sometimes removed. I have created a ticket on OmegaT source forge site. I will update the post once it is solved.
\textit{hello}
becomes something like<span data-tex=\"textit">hello</span>
quickstart.tex
from Formatting Information, an article I wrote for TUGboat, and the entire.tex
source of Formatting Information). They have replied to say they're looking at it.