I'm actually writing a Final Fantasy 1 x Pokemon fanfic right now, so this kind of autism is my jam. I made a whole party for Squall in the past, but for a 1 pokemon per party member:

Squall - Luxray easy, moody lion looking and one of his starter summons was a lightning elemental.
Rinoa - No lie her ace would be an Arcanine for Angelo, but she herself would be maybe a Swanna or Togekiss for her angel motif.
Zell - Primape cause of his energy and his struggles to keep his cool.
Selphie - Pumpkiboo line because her cutesy murder energy.
Quistis - Tsareena or Gardevoir fit her 'mature' thing she tries to keep going.
Irvine - Intellion, an emotional gunslinger who likes to play the cool guy.

Bonus:
Laguna - Boltund because he's goofy and has too much energy.
Kiros - Purloin line, just fits his vibe.
Ward - Slaking fits his vibe. Wait, Hariyama does more.

Seifer - Pyroar makes a good counterpart to Luxray.
Edea - Mismaguis just makes sense, though maybe a Gothitelle would fit more her alternative witch vibe.
??? - Necrozma, with both Dawnwing and Duskmane forms.