is there a way to preview a video with translated subtitles displayed in some way or other?
Use Subtitle Edit instead. Using CAT tools for subtitling makes not much sense as the texts are hardly ever repetitive... Plus, localized subtitles carry over the original MEANING, but are not necessary a TRANSLATION of the original message. At least in MOVIES subtitles...
Not mentioning the subtitles structure - sentences are usually broken down to separate parts and the translation does not always match the parts 1:1 (different word orders, etc.).Plus the timing - subtitles need to be timed properly, and the translated subtitles usually need to be re-aligned (so that sentences/phrases are not cut in a middle and the partial text displayed on the screen does make some sense)