Theoretically, yes, they would be valid, but not “always yes.” It would depend on other factors.
In danger-of-death situations, he can still exercise his priesthood licitly.
Other than danger-of-death, his attempts at absolution would still be invalid because absolution requires jurisdiction in order to be valid (not just licit, but valid).
As for Eucharist, it would depend on what text he uses (among other issues as well)—Anglicans are permitted a great deal of latitude in what texts they use, and we cannot say that every one of them is valid. For example, Anglicans are permitted to visit other communities and take part in their versions of the Lord’s Supper. Therefore, even though the standard Anglican attempts at consecration use valid texts, it’s not true that every text available to them does likewise. Likewise, Anglicanism as a whole permits substances other than bread and wine to be used, so in such cases, attempts at consecration would be invalid.
There are 4 sacraments that require the character of the priesthood—Eucharist, Confession, Unction, and Confirmation. I exclude ordination because that requires Episcopal ordination.
So, again excluding danger of death, the answer would actually be:
Eucharist: “that depends” but most often and most likely it would probably be valid
Unction/Anointing: No (with a “sometimes maybe” qualification)