Here is the full list of all 69 Final Fantasy X/X-2 HD Remaster achievements. It takes around 200 hours to unlock all of the achievements on Windows.
Obtain all available FINAL FANTASY X-2 achievements
Complete 100% of the main story
Obtain treasure in the Tonberry area
Complete Shinra's Bestiary
Catch the Amazing Chocobo
Win 10 times at Sphere Break
Reach the 80th floor of Iutycyr Tower and defeat the boss
Reach the 60th floor of Iutycyr Tower and defeat the boss
Reach the 40th floor of Iutycyr Tower and defeat the boss
Reach the 20th floor of Iutycyr Tower and defeat the boss
Achieve a 99 chain attack
Reach the 10th floor of Iutycyr Tower
Deal 99999 damage with one attack
Reach the highest level (LVMAX) in Gunner's Gauntlet
Defeat Trema
Obtain all dresspheres
View one complete fiend tale
Roll the same number on all the Gambler's Dice
Use Mix 30 times
Use Bribe 30 times
Learn 5 Blue Bullet skills
Open the chest that includes the Ribbon in the Bevelle Underground
Win a blitzball match in FINAL FANTASY X-2
Change dresspheres on Yuna, Rikku, and Paine in one battle
Obtain all available FINAL FANTASY X achievements
Defeat Penance
Find all 26 Al Bhed Primers
Defeat Nemesis
Complete the Sphere Grids for all main characters
Complete a Sphere Grid for one character
Learn to use all enemy abilities
Unlock all slot reels
Dodge 200 lightning strikes and obtain the reward
Obtain all Celestial Weapons
Buy every sphere at the Luca Theater
Win a race with a catcher chocobo with a total time of 0:0:0
Pass all chocobo training
Obtain all Aeons
Obtain Magus Sisters
Obtain Anima
Steal successfully with Rikku 200 times
Obtain all Jecht Spheres
Win a blitzball tournament
Defeat Vegnagun
Obtain Magical Dances, Vol. II
Listen to all of Maechen's stories
Complete an episode in Chapter 5
Defeat Zalamander
Defeat Bahamut
Help Clasko catch a chocobo by the end of Chapter 3
Defeat YSLS-Zero
Pay off O'aka's debt
Obtain one special dress
Complete the ability set for one dress
View "Eternal Calm"
Obtain Yojimbo
Defeat Yu Yevon
Defeat Seymour Omnis
Spend 100,000 gil or more in bribes
Defeat Yunalesca
Get 5 treasure chests during the Chocobo Race at Remiem Temple and win the race
View the "Underwater Date" scene
Do 9999 damage or more in a single attack
All party members come together
Win a blitzball match in FINAL FANTASY X
Learn the Jecht shot
Clear the Besaid Cloister of Trials
Find 1 Al Bhed Primer