Disclaimer: Neither George Lucas nor J.K. Rowling is writing this story.
Here are the characters in this story:
Luke Skywalker - Harry Potter (age 19), Auror Trainee, Red Five
Obi-Wan "Ben" Kenobi - Sirius "Stubby" Black (age 57), Auror Master and General, hermit
Han Solo - Ron Weasley (age 29), Captain of the Ford Anglia, smuggler
Leia Organa - Hermione Granger (age 19), Princess and Senator of Scotland
Darth Vader (formerly Anakin Skywalker) - Severus Snape (age 42), Dark Apprentice of the Death Eaters (formerly James Potter)
Wilhuff Tarkin - Pius Thicknesse (age 64), Governor of the Muggle Suburbs
R2-D2 (Artoo) - HD-WG (Hedwig) (age 33), messenger droid
C-3PO (Threepio) - W-PRC (Percy) (age 34), prefect droid
Chewbacca - Rubeus Hagrid (age 200), co-pilot of the Ford Anglia, smuggler
Owen Lars - Vernon Dursley (age 42), moisture farmer
Beru Whitesun Lars - Petunia Evans Dursley (age 40), moisture farmer
Bail Organa - Charles Granger (age 60), Prince and Viceroy of Scotland (mention only)
Wedge Antilles - Neville Longbottom (age 21), pilot, Red Two
Cassio Tagge - Evan Rosier (age 40), General of the Ministry Army
Conan Antonio Motti - Graham Montague (age 38), Admiral of the Dark Mark
Jan Dodonna - Garrick Ollivander (age 113), General of Dumbledore's Army
Vanden Willard - John Dawlish (age 60), Army officer
Garven Dreis - Rolanda Hooch (age 77), pilot, Red Leader
Biggs Darklighter - Cedric Diggory (age 22), pilot, Red Three
John Branon - Malcolm Preece (age 21), pilot, Red Four
Jek Porkins - Vernon Dudley (age 24), pilot, Red Six
John "Dutch" Vander - Herbert Fleet (age 26), pilot, Gold Leader
Tiree - Summerby (age 21), pilot, Gold Two
Davish Krail - Anthony Rickett (age 42), pilot, Gold Five
Moradmin Bast - Miles Bletchley (age 22), aide to Governor Thicknesse
Jabba Desilijic Tiure - Golgomath the Giant (age 600), crime lord
Boba Fett - Draco Malfoy (age 32), bounty hunter
Greedo - Scabior (age 42), bounty hunter
Wuher - Tom (age 56), bartender
Theron Nett - Michael McManus (age 21), pilot, Red Nine's wingman
Nozzo Naytaan - Cadwallader (age 22), Red Nine, Army lieutenent
Cornelius Evazon - Vincent Crabbe (age 50), serial killer
Ponda Baba - Gregory Goyle (age 43), criminal
Garouf LaFoe - Ludovic Bagman (age 53), informer to the Ministry of Magic
Garindan - Marietta Edgecombe (age 20), informer and spy to the Ministry
BoShek - Bem (age 28), smuggler
Nahdonnis Praji - Commander Wilkes (age 45), Ministry Commander
Pol Treidum - Cassius Warrington (age 46), Ministry Lieutenent
Shann Childsen - Eric Munch (age 48), Ministry Lieutenent
Hija - Lieutenant Savage (age 23), Ministry Lieutenent
Tanbris - Proudfoot (age 47), personal aide to Severus Snape
Daine Jir - Jugson (age 47), part of Severus Snape's personal crew
Mod Terrik - Alastor Gumboil (age 48), Hit Wizard
Davin Felth - Alfred Cattermole (age 19), treacherous Hit Wizard
Raymus Antilles - Harfang Longbottom (age 70), Captain of the Granger IV
Figrin D'an and the Modal Nodes - Weird Sisters
Laze "Fixer" Loneozner - Dudley "Big D" Dursley (age 25), mechanic
Camie - Yvonne (age 25), mechanic
Deacon - Piers Polkiss (age 19), teenager
Windy Starkiller - Mark Evans (age 19), teenager
Janek "Tank" Sunber - Gordon (age 22), Ministry Commander (mention only)
Planets:
Tatooine (Mos Eisley, Lars homestead) - Surrey (Diagon Alley, 4 Privet Drive)
Alderaan - Scotland
Death Star (Detention Block AA-23) - Dark Mark (Dark Tower)
Yavin IV - Hogwarts
Dantooine - Magnolia (mention only)
Millenium Falcon - Ford Anglia
Tantive IV - Granger IV
X-wing - Firebolt
Corellia - Devon (mention only)
Species:
Human - Human
Hutt - Giant
Rodian - Snatcher
Wookiee - Half-giant
Mandalorian - Pureblood
Aqualish - Thug
Corellian - Devonian
Alderaanian - Scottish
Tatooinian - Surreyan