It is clearly written on the checklist that translation must be certified not self translation.
So it is better to submit certified translation to avoid delays.
It is also mentioned that you can submit maximum 10 pages , so I don't know why they would need 500 pages of translation.
Exactly right. I don't know why this topic keeps coming up - the instructions are clear.
Any applicant can
risk if they wish not translating something. But for anything important, it is a bad idea. They can reject or return an application for not having the correct translations. Or just as likely, ignore any information in the file that is not properly translated.
Now, we did actually risk a few small non-translations - but very, very limited in scope. All were things that were not critical to our app but secondary or tertiary supporting information - one bank statement (but we had plenty of other good financial information); one bill for purchase and delivery of furniture (but IKEA clearly indicated); and one page each of a lease agreement and property ownership (main page and subsequent pages all legal detail). Each with short explanatory note attached.
We also did not translate passport stamps or visas, because when I looked, all of the stamps and visas had the name of the country clearly understandable and entry/exit stamps in standard date format. (Also our entire family already had TRVs from Canada for ~ten years validity so had already been examined)
I repeat: I do NOT recommend this. But in our case all of these were supplementary information, possibly more than needed, but I felt useful to include because we were compensating for other things and there were related documents (eg the lease agreement was useless on its own to establish we were living together as only in one name but we had a letter from the landlord that linked to it). Also I knew that our files would go to visa office where there is/was a high likelihood staff could read the language this was in.
Also note: our case was NOT a close case at all - married with children, five+ years together, we applied outland but already had TRVs so could have applied inland from within Canada, etc. Some of our supplementary info was to deal with minor administrative issues (we had little hard official documentation of living together, but good reasons why that was the case, and TONS of other supporting docs as mentioned).
So there are cases where one might get away with it - but don't follow the rules, you take the risks and bear the consequences. And if the information is CORE or critical to your app (as eg chats and evidence of ongoing communication likely are for lots of applicants), you should not risk it.