They would have, but their children would not have been. See Ex. 12:48. The entire household has to be circumcised in order to bring the sacrifice.
That is not exactly what Ex 12:48 says. First of all, it is with respect to the "stranger", second of all, it is with respect to "no uncircumcised person may eat of it". What it doesn't say is "the entire household has to be circumcised in order to bring the sacrifice". And how would this apply to the household of Moses, as his son was circumcised? And according to Ex 13:5, like the waving of the sheaves, the beginning point was to begin after 40 years when "the LORD brings you to the land of the Canaanite".
As for the waving of the sheaf/sheath (Lev 23:11) and Joshua, apparently upon entering the promised land, circumcised the children from the wilderness, and waved their foreskins before the LORD before offering the Passover lamb. (Joshua 5:7-11) Apparently, the harvest God is looking for is the harvest of souls, and souls with circumcised hearts, which apparently awaits for a future date. (Ez 36:24-26 & Ez 37:24 & Jer 31:31-34).
Lev 23:10 " Speak to the sons of Israel and say to them, 'When you enter the land which I am going to give to you and reap its harvest, then you shall bring in the sheaf of the first fruits of your harvest to the priest. 11
He shall wave the sheaf before the LORD for you to be accepted; on the day after the sabbath the priest shall wave it. 12'Now on the day when you wave the sheaf, you shall offer a male lamb one year old without defect for a burnt offering to the LORD.…
New American Standard Bible Ex 12:48
"But if a stranger sojourns with you, and celebrates the Passover to the LORD, let all his males be circumcised, and then let him come near to celebrate it; and he shall be like a native of the land. But no uncircumcised person may eat of it.
Joshua 5:
7 Their children whom He raised up in their place, Joshua circumcised; for they were uncircumcised, because they had not circumcised them along the way.
8Now when they had finished circumcising all the nation, they remained in their places in the camp until they were healed.
9Then the LORD said to Joshua, “Today I have rolled away the reproach of Egypt from you.” So the name of that place is called Gilgal to this day.
10While the sons of Israel camped at Gilgal they observed the Passover on the evening of the fourteenth day of the month on the desert plains of Jericho.
11On the day after the Passover, on that very day, they ate some of the produce of the land, unleavened cakes and parched
grain.