Spellsinger

He, the sweetest of those who would die, poured out his liquid voice to quench the raging hole in the sky.

– from the song of Yealan

The first spellsingers on Tellene were direct descendants of the gray elf Yealen Batania who, according to legend, created the precious metal known as mithral to fight the diabolic followers of Blacksoul. Yealen armed his Nine Saints with spears tipped with mithral heads and slew the devils faster than Blacksoul could summon them. The spellsinger sealed the gate Blacksoul had created to bring in the outsiders, and then sang a song of hope for his saints. Blacksoul devoured seven of the saints before Caregiver, Raconteur or the Eternal Lantern (the tale varies by teller) intervened and protected Yealen. Some accounts even claim Yealen reversed the summoning gate and himself sent Blacksoul away, though most non-spellsingers find this version simply preposterous.

As a spellsinger, you serve primarily as the party’s arcane spellcaster, in place of (or reinforcing) the standard sorcerer or wizard. You receive the wizard’s spells per day but the sorcerer’s spells known, and you have no need of somatic or most material components. Without the need for these components, you can also protect yourself better though the use or armor, although your martial skills are not as strong as those of a fighter’s. You can also employ your countersong ability to help block certain magical effects, but a bard’s countersong ability cannot be used to block your spells.

Essentially this class is a Wizard who does not need Somatic and Material components, but adds a verbal component to all spells, event those without one.

I have not found an adequate equivalent in 5e, let's discuss if you want to do this. Bard being full casters now could be an option, or some form of Wizard.