There is a reporting requirement for money transfers of more than $10,000 per transaction that banks and financial institutions handle automatically, but that doesn't apply to bitcoin. For IRS purposes, bitcoin is a property asset, like a physical gold coin or other commodity. You buy it at one price and sell it at another, and if you have a gain (sell for more than you paid) you owe capital gains tax.
In this case, you need to report any gift (of money or property) to any person (US or non-US) that is more than $14,000 per person per year. No gift tax is usually owed, but there is a reporting requirement on form 709.
There are no extra reporting requirements because the recipient is a foreign person.
Whether the recipient owes local tax is a matter for their local tax laws.
If they were (or will be) subject to US taxation in the future, they would only owe tax on the bitcoin when they sell it (convert it to regular money in some currency). They owe tax on the gain, which is the difference between the price you paid for it, and what they sell it for. (If you mined it, the price you paid is zero). If your friend is audited and can't prove the cost basis of the asset, the IRS will assume the cost basis is zero since the IRS doesn't have to give any adjustments or deductions that the taxpayer can't prove. So, in the event your friend is later subject to US taxation, or if their local tax laws work the same way as far as taxable capital gains are concerned, you would be helping your friend considerably by also giving them copies of the records that show what your cost was for the bitcoin asset you are giving them.
