When using the Okapi plugin for translate5 (by default activated in MittagQIs translate5 hosting) all file formats can be imported, that Okapi supports.
For example Microsoft Office formats, Indesign, FrameMaker, XML and HTML, but also numerous other file formats.
In addition translate5 supports the following different bilingual file formats for the import.
Within a zip you can upload multiple files into one task (also with folder hierarchies) and configure the task with a lot of details.
Please see the corresponding wiki page
Below you find Okapi custom file filters, people uploaded to this wiki.