Sandra Vergara came in hot as the "new girl" on last season of "Selling Sunset'' ... but she’s not afraid of a little competition -- especially if it comes in the form of Christine Quinn!

We caught Sandra rolling into SUR in West Hollywood for the GenLux Issue Release Party Thursday night, where she reacted to TMZ’s report -- producers are eyeing Christine’s possible return for Season 10 -- and Sandra says she’s all for the chaos.

Roll the clip ... Sandra admits she never fully watched Christine’s seasons, but the clips she has seen were enough to convince her the show could use that energy -- especially with Chrishell Stause stepping away and leaving a villain-sized vacancy.

Sandra even joked she’d def want to stay on Christine’s good side if she comes back ... so hit play to hear her full take ... including her thoughts on Jason Oppenheim’s recent split from Jessica Vargas.

TMZ broke the story of producers having early talks about bringing Christine back, but nothing locked in yet ... but if Sandra’s vote counts, the drama’s already been approved!