Learn English – Is it grammatically correct? “You can choose which one to show to users either A or B.”

None of those is right!

The correct sentence is "I have a bag like yours." No apostrophe.

"I have a bag like you have" might be considered an informal elision of "I have a bag like the one that you have", but I would never use it in even slightly formal speech.

If you are one of those people who defer to etymology, then 'either' comes from the Old English ǽghwæðer, "each of two" (i.e. "both"). By the 13th century, the meaning had shifted to its present sense of "one of two". So the word has a history of gradual change. Shakespeare wrote "They say there is divinity in odd numbers, either in nativity, chance, or death" (The Merry Wives of Windsor" c.1597) (an odd number of items, naturally). The "one of two" meaning is relaxed, according to a number of dictionaries, when introducing a list (like the food items in the question), but tends to be more strictly applied when using 'either' as an adjective - "I'll marry either girl, Mary or Jane", or a pronoun - "either [of them] will do". There is a similar story for "neither". The safest advice is to stick to "either of two", and use e.g. "one of" for more than two items.

Either (Grammarphobia)
Either (Etymonline)