Hello,
I recently bought this set: https://www.lovehoney.co.uk/product.cfm?p=39437 for my partner but she doesn’t like G strings but really likes the colour of the set and the look of it. Does anyone have any suggestions about any underwear that could be used as an alternative that would match well with the set?
I bought the set not realising it was a G-string, silly me!
I think anything black would work. 
I agree with @Ian_Chimp, black undies would be your best bet. I had a quick search of the site and there’s lots of options. I’d totally recommend a pair that has a little bit of lace too. Let us know what you go for 
Maybe these?
She is a lucky lady looks very nice, I have done that before got a nice set not knowing it was a gstring.
That’s was ok though as I had it 
Hi, I think you could team it up with any sexy black lacy briefs if you wanted to, although I’ve recently had Lovehoney’s quarter cup bra and briefs set in red, but there’s also a stunning black set too, the briefs that come with this set are really gorgeous and well worth a look, your wife might love them.
Hope this helps.½ cup bra set???
Stunning set! As everyone else has said, I’d pair it with black knickers (maybe lace or mesh and either thong, briefs or cheeky shorts)
@Curums123, what a lovely set!
Luckily, the suspender straps are attached to the belt and not the g-string, so as others have said any pair of black (the blue would be difficult to match) lace or satin knickers would be great. They could even be worn over the top of the suspender straps for easy removal (I think these sets often include g-strings because they can be pulled to one side, which isn’t so easy with fuller briefs).
Even just black cotton bikini briefs would be fine - the rest of the outfit attracts all the attention!
Black is your obvious option as others have said but commando would also work well