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