I think you are misinformed: the electrochemical reaction used by continuous glucose sensors relies on a glucose-specific enzyme and it doesn't have anything to do with lactate. Lactic acid strips use a completely separate enzyme/reaction.
Hat tip to you and sibling comment about continouous lactate sensors (seem like they are microneedle/patch based?). Quick review shows minimal clinical evidence, but maybe that's sufficient for the consumer wearable market.