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