I'm not sure specifically about 'pewdiepie x cry fanfic'. You could try searching on some fanfiction websites like Archive of Our Own. They might have relevant works if they are within the site's guidelines.
There could be some out there, but it might be a bit difficult to find the really good ones. You may have to look through various fanfic communities. However, keep in mind that not all fanfics are of high quality, and some might deviate a lot from what you expect in terms of the portrayal of the characters.
Finding a great 'pewdiepie x cry fanfic' can be a challenge. First, you need to know where to look. Some popular fanfic platforms are likely to be your best bet. When you start looking, read the summaries and reviews if available. This can give you an idea of whether the story is something you'd be interested in. Also, be prepared to sift through a lot of content to find the gems.