SEO required with polish language skills

A London Law firm would like to hear from SEO experts who can help improve the organic search results for a polish language website they rank. The firm is very well known in the polish community, offering personal injury services. The firm launched a polish language website a number of years ago with a more recent refresh. The site is a wordpress site. The firm would like to see the site rank for certain keywords and is looking for an seo to help take this forward. As the website is written in polish and the keywords are also polish it would make sense for this person to have polish language skills.