Offset mortgages

I’m in a situation where we need to buy larger home. I will need to sell my current home (mortgage free) and take out a loan from the bank to buyer the house.

I have being offered a offset mortgage. Where we can use our saving or savings of family members to cancel out the interest portion of the loan. It is possible to cancel out 100% of the interest of the loan and just pay the capital amount borrowed. Would this be considered shariah compliant?