I already finished my Master's degree a while back. Now I am applying for Ph.D. programs and a lot of them require some academic publication, and since I only have a Master's thesis I don't know If I should translate it.
If you haven't given up copyright to it, then you are within your rights to provide a translation. Just mark it as such, citing the original. There are no problems with this.
If you have given up copyright (say, to a publisher) then they hold the rights, but will probably give you permission (a license) to do this. But it doesn't count as a second publication - just as a translation - since the content is the same. In some cases, your agreement with a publisher may already include this right.
It might make your work more accessible to an application committee, of course.