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Alex Gregory, Andy Triggs Hodge, George Nash and Moe Sbihi make up a new-look men's coxless four crew.
Olympic and world champion Helen Glover renews her partnership with Polly Swann after Heather Stanning withdrew from consideration on medical advice.
A team of 50 rowers across 17 boat classes will contest the event.
For the last 18 months, Britain have made the men's eight their top boat, culminating in a first ever gold medal at the World Championships last year.
However, with the Rio 2016 Olympics only two years away, men's head coach Jurgen Grobler has chosen to put his four best rowers back in the four, the boat which won gold at London 2012.
Gregory and Triggs-Hodge, who won gold in the four in London, will be joined by Nash and Sbihi, whose performance at the trials has seen their promotion.
Glover and Stanning were impressive at trials, but eased off in the final part of the race as Stanning, having only returned to the sport in December following a six-month stint in Afghanistan with the army, struggled at the top intensity.
As a result, Swann, who won world gold with Glover, returns to the pair - the team's top women's boat - for the regatta in Serbia.
Tanner added: "We are in an enviable position with our open women's squad. "Helen, Heather and Polly are a strong triumvirate for the women's pair seats and it was always a tough call to make.
"We simply need to get Heather to step back off the training a little, rebuild and come back stronger later in the season".
Olympic champion Kat Copeland, who returned to competition for the first time since London 2012 with victory at April's trials, has been teamed up with 2013 world finalist Imogen Walsh.
Five Olympic medallists - Pete Reed, Will Satch, James Foad, Matt Langridge and cox Phelan Hill - have been named in the men's eight.
Great Britain have named 15 Olympic medallists in the nation's first ever European Championships squad for the regatta in Belgrade from 30 May-1 June.