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