After a bruising, hard-fought opening, Walsh’s try set the tone as debutant Mark Nawaqanitawase shifted the ball left for the rampaging Brisbane Broncos full-back to go over in style.
England were unhappy as scrum-half Mikey Lewis appeared to be tripped in the build-up, and there looked to be a forward pass too – but the try was given following a review by video referee Jack Smith.
Smith partly redeemed himself to the Wembley crowd by disallowing a second Australia try before the break as Dom Young was taken out by Josh Addo-Carr as he jumped to catch a high kick.
Wane’s side initially responded well to conceding and defence-splitting grubber kicks from George Williams and Tom Johnstone had the green and gold defence on their heels.
But Nathan Cleary added a penalty with the last action of the first half to put Australia 8-0 up – and they extended the lead straight after the interval.
After putting the hosts under constant pressure from the restart, Angus Crichton strode through to score with full-back Jack Welsby too deep and allowing him to go through far too easily.
Australia kept England at arm’s length thereafter, easing their way to victory in the first meeting between the sides since the 2017 World Cup final.
That success was secured with 15 minutes remaining as second row Crichton scythed through the defence again for his second try, and more gloss was added when a superb field-length move down the left was finished by Walsh.
Daryl Clark barged over in the final minutes for England, but it was no more than a consolation.
A downside for the visitors was that captain Issah Yeo was forced off in the first half after failing a head injury assessment following a clash with Young. He will also miss the second Test on Saturday (14:30 GMT) at Hill Dickinson Stadium in Liverpool.
There were some positives for England.
Williams and Lewis started as the half-back pairing for the first time, with Harry Lewis left out of the squad, and fitted like a hand in glove. Expect them to repeat their duet in Liverpool next week.
There, England will continue a quest for a first win over Australia in three decades, and try to rescue a first Ashes series triumph in 55 years.