Thank you for the help. I could solve all the issues and install the module successfully, but now I got an error:
Internal error, more info in console log!
Fatal error: Uncaught Exception: Error: Table 'euromag_euromagnet_hu.oc_translate_expert_same_translations' doesn't exist<br />Error No: 1146<br /> select t.attribute_id, t.language_id language_id_from, l1.code language_code_from, t.name text_from, l2.language_id language_id_to, l2.code language_code_to, l2.image language_image_to, t2.name text_to, count(*) value_count from oc_language l1 join `oc_attribute_description` t on l1.language_id = t.language_id and true and REPLACE(REPLACE(REPLACE(REPLACE(t.name, ' ', ''), ' ', ''), ' ', ''), ' ', '') <> '' and t.name is not null join oc_language l2 on l2.language_id <> t.language_id and (l2.language_id = 7) left join oc_attribute_description t2 on t2.attribute_id = t.attribute_id and t2.language_id = l2.language_id left join oc_translate_expert_same_translations stt1 on stt1.language_id_from = l1.language_id and stt1.language_id_to = l2.language_id and stt1.text_hash_sum = unhex(MD5(REPLACE(REPLACE(REPLACE(REPLACE(LOWER(t.name), ' ', in /mnt/buffer.2/srv/www/euromagnet.hu/website/system/library/db/mysqli.php on line 40