Can fix various ways, so here's one more:
Crossbows get two factors to them:
Crossbows are built to specific strength bonuses. Said strength bonus applies to damage in the first 5 increments, as well as to hit in the first two.
A crossbow of strength bonus one higher than the wielder's increases reloading time by two steps. Two or more is impossible to reload, but can be fired.
Loading Mechanism is one of four:
Repeating: Simple, base die d6 No-Action until empty[10 shots], Full to swap magazines.
Lever[Light]: Simple weapon, Move action to reload [free with Rapid Reload]. Base die d8. Allows strength factor +2 over your own, without penalty.
Stirrup: Full action to reload [Move with rapid]. Base die 2d6. Allows strength factor +4 over your own without penalty. Martial weapon
Cranequin [for steel-prod arbalests or the such]: A bloody winch. Base die 2d10. Allows strength factor +6 over your own without penalty. 3 full actions to reload [1 full with rapid reload]. Martial weapon
This does make FINDING a crossbow in a dungeon an iffy affair as to whether or not you can use it [For example a strength 18 fighter could use a +4 strength bonus repeater, +6 lever, or +10 winched arbalest, but a strength 12 character hoping to use a +4 bonus crossbow with a goat's-foot lever is taking a full action [move with rapid reload] to reload the bloody thing.
Adaptive would give the type, adjusted to your strength, but would do nothing for what kind of reload actions it requires; if it's got a winch it's got a winch.