I went back to a Beta save and tried to see if it was an issue there. It wasn't as you can see in the screenshot I would have been able to "Approach to Sign"
Edit: Went back in and tried to see if it was an issue with other leagues. I've one seen this problem in the Japan leagues (J1, J2, and J3)
Edit 2: More testing, because why not. This issue may be confined to the starting unattached players. I released Ogasawara through the Editor and was given the option to approach to sign like normal. Simmed ahead a year in the future to see what happens to other released players, and I was able to sign them