You are imposing onto the word, "God" what Trinitarians do not. You are taking "God" as a "name" solely used of the Father. But "God" is not actually a name, nor is there necessarily a one-to-one equivocation with "the Father."
While it is true, "God" can be used in reference to the Father, it is not strictly used of the Father.
You asked, "Where is Jesus called God by His Father?" Well, how about the verse you just cited? Hebrews 1 is a "Father to Son" dialogue between God the Father and the Lord Jesus, and three times in the discourse, is Christ spoken of in ways that only the God of Israel can be.
In the pre-Christian Greek version (otherwise referred to as the LXX) of Deuteronomy, the Lord claims He alone is God (32:43). The overall theme is a warning to Israel not to abandon Him for any other god (31:24–30),
“They provoked me to anger with strange gods; with their abominations they bitterly angered me. They sacrificed to devils, and not to God; to gods whom they knew not: new and fresh gods came in, whom their fathers knew not. Thou hast forsaken God that begot thee, and forgotten God who feeds thee. And the Lord saw, and was jealous; and was provoked by the anger of his sons and daughters, and said, I will turn away my face from them, and will show what shall happen to them in the last days; for it is a perverse generation, sons in whom is no faith. They have provoked me to jealousy with that which is not God, they have exasperated me with their idols; and I will provoke them to jealousy with them that are no nation, I will anger them with a nation void of understanding. For a fire has been kindled out of my wrath, it shall burn to hell below; it shall devour the land, and the fruits of it; it shall set on fire the foundations of the mountains.” (Deut. 32:16–22 LXX Brenton’s English)
And again,
“and the Lord said, Where are their gods on whom they trusted? The fat of whose sacrifices ye ate, and ye drank the wine of their drink-offerings? Let them arise and help you, and be your protectors. Behold, behold that I am he, and there is no god beside me: I kill, and I will make to live: I will smite, and I will heal; and there is none who shall deliver out of my hands. For I will lift up my hand to heaven, and swear by my right hand, and I will say, I live for ever. For I will sharpen my sword like lightning, and my hand shall take hold of judgment; and I will render judgment to my enemies, and will recompense them that hate me. I will make my weapons drunk with blood, and my sword shall devour flesh, it shall glut itself with the blood of the wounded, and from the captivity of the heads of their enemies that rule over them. Rejoice, ye heavens, with him, and let all the angels of God worship him (καὶ προσκυνησάτωσαν αὐτῷ πάντες ἄγγελοι θεοῦ); rejoice ye Gentiles, with his people, and let all the sons of God strengthen themselves in him; for he will avenge the blood of his sons, and he will render vengeance, and recompense justice to his enemies, and will reward them that hate him; and the Lord shall purge the land of his people.” (Deut. 32:37–43 LXX Brenton’s English)
Notice the language in 32:43 (LXX),
καὶ προσκυνησάτωσαν αὐτῷ πάντες ἄγγελοι θεοῦ
The author of Hebrews picks up on this language which was originally applied to YHWH, and appropriates it to Christ. The LXX is cited verbatim:
καὶ προσκυνησάτωσαν αὐτῷ πάντες ἄγγελοι θεοῦ (Hebrews 1:6)
καὶ προσκυνησάτωσαν αὐτῷ πάντες ἄγγελοι θεοῦ (Deut. 32:43 LXX)
Hebrews 1:6 is thus rendered,
"And when He again brings the firstborn into the world, He says, 'AND LET ALL THE ANGELS OF GOD WORSHIP HIM.’” (Hebrews 1:6)
On this note, there is a textual variant found in some ancient copies of Deut. 32:43 LXX. Some mss substitute υἱοὶ (“sons”) in place of ἄγγελοι (“angels”), and therefore reads,
καὶ προσκυνησάτωσαν αὐτῷ πάντες υἱοὶ θεοῦ
Regardless of the variant, the grammar — in either instance — correspond one-to-one. They both begin with the word, και. They both use the third-person imperative for the verb to “worship.” Regardless of the nominative noun used — ἄγγελοι or υἱοὶ — they are both anarthrous. And they both use the genitive second-person pronoun, θεοῦ (“angels of God”).
For these very same reasons, Ps. 97:7 is not likely the reference of Hebrews 1:6’s citation. Ps. 97:7 does not begin with και. It uses a second-person imperative (not a third-person imperative) for the verb to “worship.” It uses the articular ἄγγελοι (where Hebrew 1:6 is anarthrous). And it uses the genitive third-person pronoun, αὐτοῦ (“angels of him”).
Witnesses will tend to give all sorts of excuses of why προσκυνησάτωσαν should not be translated “worship,” but fail to place the original words back into their OT context, and understand them through that lens. One cannot argue that Heb. 1:6’s use of προσκυνησάτωσαν is any different than that of Deut. 32:43 LXX, especially in light of the fact that Deut. 32:43 LXX is what’s being referenced in the very verse. Not to mention, this is one of three Septuagint-YHWH texts cited in the discourse (1:6, 1:7, 1:10–12).
Then in Heb. 1:10-12, the Father refers to the Son as the one who brought forth creation.