Below is a round-up of the birth announcements from British newspapers. Sources include a national paper (The Telegraph, The Times) and a broad range of local newspapers from across England, Wales, Scotland and Northern Ireland.
Sibling names are in brackets.
Boys:
Alden Peter Theodore (Inigo Norton Sebastian)
Alexander James Daker (Charlotte Alexandra Eden)
Arthur Inigo Dixon (Leo Walter Langdon)
Alfred Louis
Archer George Edmund
Arthur James
Arthur John David
Brodie Alexander (Orla Jane & Ben Patrick)
Charlie Merlin
Eden Bo (Etta)
Elis Llywelyn (Martha Elen)
Fergus John (Eliza Catherine)
Frederick John (Caragh Isabella & Edward Peter)
Frederick William
George David (Rose Ottilie)
George Paul Stephen (Poppy Isabella Mary)
Gregory Frederick (William Ernest Hugh & Ralph Christian Curtis)
Henry Graham Barker
Henry John Allenby
Indiana Newsum (Hunter Dempster)
Jack William Arthur (Georgina Mary Ella)
Jacob Michael
Jacob Patrick
James Thomas
Louie Ralph
Louis Oliver
Louis Tristan Olivier (Leo Arthur Louis)
Ludo Ziggy Powys
Maximilian Guy Michael
Milo Hal Flint (Logie)
Montgomery Mitchell Findlay
Noah Patrick
Oscar Andrew Francis (Edward)
Patrick Ronald Hugh
Rafferty Benjamin Guy
Rupert Charlie Joseph
Stanley Michael James
Wilfred David
Girls:
Alana Cherise (Aamiya Louise)
Alexandra Grace Margaret Christine
Arabella Prudence Morley
Ava Grace
Belle Elizabeth
Charlotte Elodie
Coco Fleur Hayama (Otto & Posy)
Daisy Victoria Rose
Delilah Deere
Eleanor Alice (half-sibs: Oscar, Ollie & Rosie)
Elisa Alexandra
Emilia Rose (Charlotte Victoria)
Emma Seren (Juliet Lily)
Eveleen Kitty
Flora Elizabeth (Margaret "Peggy" Anne Rose)
Florence Elizabeth
Harper Lily
Isabel Jane (Lara Daisy)
Isla Jane (Ezra)
Jemima Florence Hester (Wilfred Henry Atticus)
Lettice Amelie (Florence)
Lily Alice Eve
Lily Hope Maud
Lucia Beatrice India (Leo Arthur Pownell & Alexander Louis Prospero)
Mabel Beryl
Maisie Elizabeth (Alexander "Xander" Hugh & Esme Jane)
Marsaili Barbara
Olympia Alice Vanda
Ramiyah Zosha
Silvia Isobel (Tabitha Juno)
Sylvie Jean Anna
Tabitha Grace (Montague "Monty" George)
Winifred Sophia
Xenia Phoebe Grace
Twins:
Eloise Iris & Sophia Agnes
I cross-reference older BAs to find the full names of the siblings, however often they are missing (especially the eldest siblings, or for half-siblings) which explains why you will sometimes see something like: George Henry (Lucy, Emma & Jack Arthur). "Lucy" and "Emma" may well have middle names as well; I simply cannot find them online.