He used a hood and sunglasses to conceal his face.
When police arrested Moorhouse outside his home in Parramatta on Wednesday morning, they found him with a camera similar to those found at the stations. A number of items were seized for forensic tests following a search of his home, police said.
Moorehouse's lawyer indicated he would plead guilty to all offences, including two instances when a child under 16 was filmed.
Police allege Moorhouse installed a camera underneath the sink in the bathrooms. Almost 100 people were filmed at a Parramatta train station toilet between February 13 and 14, while another 23 were filmed on the morning of February 10 in a toilet at North Sydney station, it is alleged.
Police said the cameras were found by train staff.
It is alleged about another 100 people were filmed in a Westfield Parramatta disabled bathroom between March 17 and 20.
Moorhouse has been granted strict bail and is due to face court again on May 31.