If some of my incoming links come from different languages & countries sites, can that be harmful or have a negative impact on my Google ranking?
Like links from sites on .cn, .ru, .jp, etc. when my site's language is English.
Does Google allow incoming links from different languages & countries?
Yes Google will allow you to have incoming links from international websites and will not penalise you for that as long as you avoid participating in link schemes that goes against their guidelines.
They also have declared that any backlink coming from a bad reputation source will be demoted rather than penalised.
However, you have higher chances to get penalised if your website is in the US because algorithms are made for the purpose to "fight" primarily against USA-English spammers.
So my advice is to make sure your website targets/reaches a clear international (global) audience that will benefit from the reference made by those linking to you. If you are a USA website focused on the USA market that just happen to have several backlinks from other countries as long as these links are legit you don't need to worry at all.
As you may know, the relevance is the key in SEO these days.
Backlinks in English to English might not be effective if they are not relevant.
The Same strategy should be there too.
You may think about the natural process. Example: Let's say if there is a website (English) which may have very useful info about SEO tips and if there is a blogger and his blog may be in different language talking about SEO and if he may link SEO tips websie, it should be fine. Firstly because this doesn't happen too often so link volume will be very less. And Google may be able to relate.
Now, if you are planning to get backlinks in an unnatural way then forget about other language even English to English may not work.
So, relevance is the key.
