Bilingual invitations can be technically tricky but not impossible. We've worked on bilingual invitations before (as pictured above) and thankfully nothing was lost in translation. If you can supply us with the exact text, we may be able to assist you.
One thing to consider is that unfortunately there are very limited accessible font choices for different languages other than English. A lot of the fancier script fonts for example will not support special characters. One way to get around this is to hire an actual letterer/calligrapher to write out the words you'd like and we can scan that in and place it into the design.
Please don't hesitate to contact us if you would like to see if we can help you with your bilingual invitations, we'd love to try and help you out!