Blue
Ravenous Bugblatter Beast of Traal
Well, nothing MAD. Hmm, if you go for a race with +2 DEX you can get a 15 DEX and 13 CON, which is playable, especially with DEX being useful in many different ways. I'd suggest some sort of archer, but if it's fighter, rogue, ranger, or a multiclass.Any thoughts on race/class/build for these stats above (bolded)? I need some ideas for my backup character. All official content plus UA permitted. Feats/multiclass okay.
You won't have the ability scores to spend lots of feats on SS and crossbow expert so you won't be a DPR king.

I'd start with a level of fighter - Archery style can boost your attack roll, with a +2 Dex mod medium armor will give you the best AC for now, and you can change it later. Plus fighter MC never hurts for martial characters. Each level is good. Go rogue from there if you want, or stay fighter.
Alternately, the UA Ranger beastmaster would be an interesting replacement. Because a good part of the heavy lifting is now on your companion's ability scores and not your own. And you can still use archery.
Instead of a +2 DEX race, vHuman gives +2 mods for DEX and CON and an archery feat.
Of course, you could also ignore your two best scores and go for a moon druid. Replace all your physical scores when you get up to wildshape. With a wisdom of 11 you'll have to focus your casting on buffs and healing when not in form, but that's viable if restrictive. IIRC the starting party has several neggative CON people. Goodberries dished around to everyone in the morning can be a quick feed to get people back on their feet. Efficiet, and can be delivered by whomever, not just on your initiative.