Is the city of Baldur's Gate even accepting goblins? Let alone murdering those on sight like any (mostly) hostile monsters?
A goblin's reception would depend a lot on how they're presented and to whom. I guess we're talking Flaming fist mercs and city dwellers, and it's hard to say because it comes down to the individual level. A merc might as easily be hostile as want to keep the peace, then there's orders.
I'd say that the reception would be better than frontier homesteads that have suffered raids. BG's high level of security might make goblins more a curiosity than a threat. However, in this timeline Elturel suffered greatly and a ton of refugees have made their way to Baldur's Gate. If the Tieflings' suffering is anything to go by, goblins will not be wholly safe in the outer city where refugees are forced to live.
Back to how they're presented. If they're part of a group and appear to be more or less equals, they're going to stand out but be extended some benefit of the doubt. In some areas of the city like the wizard areas or that Gond museum, they might be considered even mundane. I'm sure I've read of wizards with goblin (or more strange) helpers.
As it is, the whole party in BG3 might get a very hostile reception due to the city's situation, and being goblin or not is moot.
