I'm not interested in translateling just the literal meaning of FYI. I'm interested in if there is a phrase that fits the same nuance.
Some English examples.
To Spouse: "Oh, FYI, Jill is bringing the wine".
To Co-Worker: "FYI, that meeting has been moved to 4pm"
To A Friend: "FYI, the Toyoko-Line is closed for repairs so you should probably take the Meguro-Line"
"FYI" is a very casual phrase in the situations above. Maybe "ところで。。。。”? Although I don't know if you can use "ところで。。。” at the start of the conversation. Every example I've been taught is always in the middle of a conversation when wanting to suddenly switch topics.
I came here because I typed "FYI" into Google translate and it said "ご参考までに” was the "community verified" translation but that seems not to fit the same nuance as FYI.