Homes and businesses divided by Irish border | UK News | Sky News
This news report claims to show a residential house that is partly in the UK and partly in the EU, but frustratingly gives very little detail that could pin down the location.
There’s a very long article here: House divided - 2019 - PLeary.pdf (brookes.ac.uk) about a house that straddled the border between Northern Ireland and the Republic until it was knocked down in 2009. It apparently became quite famous.