The "TWD97" datum uses the same ellipsoid as the "WGS84" datum, which is effectively the same as the default "ITRF00" used in the WL. Your data already contains lat, lon numbers, so you can simply import the data and feed it to GeoPosition (ToExpression is needed to convert the strings to numbers):
positions = GeoPosition[Map[ToExpression, {"TWD97Lat", "TWD97Lon"} /. Import["~/Downloads/TLSA.json"], {2}]];
Then you can use it in any of the geo functions, like
GeoListPlot[positions]
GeoGraphics[{Red, Point[positions]}]
etc.