same ip address different country mailing address

1.) is it OK to check my adsense acct and check a relative or friends acct on same ip address but their acct mailing address is in another country?

this is different from same ip, same physical address.
it is same ip, different language, different address

basically setting it up for friend traveling abroad so they can make some extra money?

2.) Also, is it OK for 1 site of mine to link to their site, both of these sites have the same theme.

nothing illegal just simple SEO, advertising and "always" white hat stuff.

 

I'm not sure about #1, but #2 should be fine. Just don't click on each other's ads.

 

So, I should just ask them to change the address to match mine and it'll be OK for #1?
OR I do not check theirs at all?

They don't have USA bank acct and want to receive money in their currency.

 

Google doesn't allow the mailing address to be changed to a different country for many accounts, so changing the address probably isn't a good idea. I really don't know what the best solution is.,