Usuthu are currently worrying more about survival than going for league honours, so earning a CAF Champions League spot is off the cards for the Durban-based outfit this season.
However, AmaZulu can qualify for the second-tier Confederation Cup if they win the Nedbank Cup.
Johnson's side will host Highlands Park in the last-32 of the domestic competition at King Zwelithini Stadium tonight (20h00).
"I would like to see AmaZulu competing in Africa, so we would like to win this tournament," said Johnson, who contested the Confed Cup with Platinum Stars in 2017.
"I've competed in Africa with Platinum Stars, it would be nice to do it again."
He added: "Playing in bigger tournaments outside the country, it helps in terms of football growth.
"Anyone would benefit from playing in CAF competitions."
Johson, though, expects a tough game against Highlands, who they beat 2-0 in Tembisa before playing to a goalless draw in Umlazi in the league on January 12.
"We are facing a team that we should've beaten in the last encounter," he said.
"We also gave them their first loss at their home stadium.
"Surely they will come out firing, especially as they are on form."