Is my phoenix team enough powerful for thrawn/palpa events?

Put them preferably at level 85.
Do the updating of the skills, especially the unique ones putting the omegas will help a lot against the GAT.
Improve modifiers. Speed, and speed arrows in the secondary of other mods in all.
You can keep them G8, if you have to put someone other than the G8, that is Erza that fits in other times for being a Jedi DPS, the others are not worth the investment.