We have a woocommerce site with around 40 plugins, We have a custom language translator / plugin that uses qtranslate and a bing translate widget.
When visitor visits the site it auto detects the users browser language and changes site language.
This only works for some users. For others, on their first visit the language will not change either auto or if they select from the language dropdown. If these selectagian from the dropdown all works fine and for the future.
Also, product pages don't open fully (dropdowns don't function and images scroll doesnt work. The above 2 issues are definitely a related problem.
Of the 40 plugins we have, we have disabled 37 of them including all caches and just left woocommerce, qtranslate and the language plugin, but still we have the issue, so the problem is either in 1 of these 3 plugins or the theme / child theme.
You need to use a mac computer or have access to mac, as this is where the issue mainly happens and you need to be a woocommerce expert with excellent front end skills and bug fixing experience.
Budget is $50