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If your wife is the sole owner of the property, all the rental income will be assessed on her. She clearly has a significant amount of unused personal allowance so the tax liability would be lower. Losses on overseas properties cannot be relieved against profits on UK properties as you will read here.
The problem you have is that the mortgage company will have a problem because your wife has a low income. You may have you act as guarantor. In addition, there may be a stamp duty charge on the mortgage transfer as you will read here.
I hope this helps but let me know if you have any further questions.
You could execute a deed of trust to try to separate the income and capital rights but HMRC don't like it and I know some lenders don't. Take a look here for information on deeds of trust and consider consulting a solicitor as its more of a legal question than a tax one. In particular, read the notes under the heading "Form 17 rule" here.