If raw eggs are nearing their expiry date, can they be preserved in the freezer? Would there be any issues with them after taking them out of the freezer?
If you're going to use the egg yolks without freezing them you'll typically need to use them the same day. I sprinkle a little water over them before covering and putting in the fridge to help keep them from drying on top.
You can freeze them but you'll need to add corn syrup (or make a simple syrup of sugar and water) and stir it into them before freezing. You'll need to use about 1/4 teaspoon per egg yolk.
Egg yolks cannot just be frozen on their own because the water in them freezes and causes the proteins to form tight clumps. The result is that when they are thawed they have firm gelatinous texture. I've tried the salt and sugar recommendations alone and find that they don't work, probably because neither has a chance to really dissolve and act to keep the water and proteins combined.
Using the corn syrup will ensure that it is evenly blended through (provided that you stir it in well). When I make an angel food cake I will do this by adding 2 tablespoons of corn syrup to a cups worth of egg yolks (about 12). Divide it into smaller containers though as you'll just waste it if you freeze it in batches bigger than you're likely to need. 1 tablespoon of the mixture is roughly equivalent to 1 yolk. You'll of course have to use it in recipes that would be sweetened such as custards, ice cream, etc.
Eggs can't read calendars and so the expiration date is only a guide. Properly handled, they will keep just fine for several weeks or longer past their expiration date. Their quality will slowly diminish primarily due to water loss. You can judge the age of an egg by placing it uncooked in a glass of water. The larger the air cell, the more internal water has been lost, and the egg will stand more upright at the bottom of the glass. If the egg is rotten, it may float. Don't leave the egg in the water, of course.
An egg that's been around a little while (it's usually long enough by the time you buy them at the grocery store) will make peeling boiled eggs easier than if you use eggs fresh from the hen.
There may be some recipes that are more sensitive to an egg's age, but I wouldn't use frozen eggs in them anyway.
Milk, on the other hand, is quite adept at calendar reading.