If you are looking for RAships in a country in which you are not a citizen, be sure to check that your citizenship is eligible for RAships you are considering. Some RA positions in the U.S., for example, are open only to U.S. citizens and permanent residents. This tends to be true of federal government positions and positions that require accessing protected federal data.
Larger groups that take on many RAs (sometimes called “labs”) are more likely to offer visa sponsorships. Institutions and PIs focused on work in developing countries may also assist in sponsoring travel visas if travel is essential for the work. However, smaller groups and faculty members who take on fewer RAs may not be able to sponsor visas.
Here’s one tip: to save yourself administrative hassle, be aware of your country’s guidelines on work visas and do your best to keep track of your visa requirements. For instance, make sure that your passport is not about to expire when you are applying for your visa. Some countries require your passport to be valid 6 months after the visa start date!