With difficulty:

1) Use as many visual techniques as possible e.g. Screen sharing and drawing pictures and sketching examples of what you're talking about.

2) open chat channels all day

3) ability to build rapport e.g. During standup calls look at what the weather is like in their country or share something about what's happening in your area at the weekend. Ice breakers if you will

4) if possible get them to visit you so they understand the culture in your office and understand the people. the most success we've had is when people visit the local team soon after joining