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