Yes you can achieve the report in multi-language please refer sale order report

<template id="report_saleorder">

        <t t-call="report.html_container">

            <t t-foreach="doc_ids" t-as="doc_id">

            <t t-raw="translate_doc(doc_id, doc_model, 'partner_id.lang', 'sale.report_saleorder_document')"/>

    </t>

    </t>

</template> 

You can print report in partner language using template.

Also you can define the po file for the words are used in your report. In Setting->Import/Export->Export Translation where you can export the translation file of your module and put that file into i18n folder. then upgrade the module and load the translation again you will get the translation words from the po file.