1/2" Brass Chrome 3 Way Diverter, Hose Fitting Tee, T Shape Adapter Connector for Angle Valve Hose, Bath Shower Arm, Toilet Bidet Sprayer Faucet

It looks like you need a 1/2" x 1/2" x 1/2" T-valve, instead of the one 7/8" one that is standard in the US. Here is an example of one on Amazon: https://www.amazon.com/dp/B0156FHJ7A?ref=cm_sw_r_cp_ud_dp_N535494VVHD5QDKSXQ2E&ref_=cm_sw_r_cp_ud_dp_N535494VVHD5QDKSXQ2E&social_share=cm_sw_r_cp_ud_dp_N535494VVHD5QDKSXQ2E&_encoding=UTF8&peakEvent=5&dealEvent=0&th=1