By TRA “express” (slow legacy train system): 14 to 16 min.
By TRA “ordinary” (even slower legacy train system): 24 min.
163.29.3.96/TWRail_en//index.aspx
HSR doesn’t stop at Changhua. A station is planned.
Were I you, I would live near a TRA station in Taichung. The trains are packed during business rush hours and school rush hours. The standing room in reserved cars in also packed with “interlopers”. I would pay that “commute” price to live in Taichung.