Lonergan said the date, opponent, venue and broadcast details for the card would be unveiled in coming days.
“Mea will be headlining the biggest boxing show in New Zealand this year,” he said. “That much I can confirm.”
Capturing the IBO title would merely be her first step towards global domination, Motu said.
“I’m coming for all the titles – and I’m not stopping until I have them,” she said.
Victory in April would put Motu on a collision course with undisputed Puerto Rican featherweight champion Amanda Serano – who holds the IBO belt at the higher weight division.
Other big names to hold IBO titles include Oleksandr Usyk (heavyweight), Gennady Golovkin (middleweight) and Alycia Baumgardner (super-featherweight).
“The chance to fight for world title at home is a dream come true,” said Motu. “I’ll be fighting for my whanau and everyone who has helped me along the way.”
Motu’s trainer Isaac Peach said his charge’s time had well and truly come.
“Mea’s beaten everyone there is to beat in her own backyard,” Peach said. “In her last three fights she has stepped up to face international opponents and has been every bit as dominant. So, yeah, she’s ready.”
Peach will be cornering a second world title challenge for one of his fighters in the space of couple of weeks – following David Light’s showdown with Lawrence Okolie for the WBO cruiserweight title at Manchester Arena on March 25.
Peach, who also trains undefeated prospects Andrei Mikhailovich (19-0) and Jerome Pampellone (15-0), said Motu was well worth her main event billing on April’s show.
“Mea is not only talented but she is hugely entertaining – which is a massive factor in boxing,” Peach said.
“She’s a main event fighter, not a support act, so this fight will be the main event regardless of who else is on the card.”