Here are the conversions that I've done so far of non-homebrewed material. You may recognize them from the 2e Tome of Magic, various FR sources, the 3e BoVD and the 1e PH.
EDIT: Oops, missed
Alustriel's banner!
Alustriel's Banner
2nd-level illusion (Art domain, bard, paladin, sorcerer, wizard)
Casting Time: 1 action
Range: 120 feet
Components: V, S, M (either a real trumpet or horn or a tiny model of one made out of bone, ivory, whittled wood or metal)
Duration: 10 minutes
This spell causes an impressive fanfare to sound as a banner appears in midair wherever you desire within range, even high in the air. The banner may be of any size up to 30' on a side and of any appearance desired, from rigid and shield-like to a long flowing pennant, and can look new or ancient. The banner can emit a glow if you so desire, as if subject to a light spell. You may have the fanfare either be an original composition or yours or one that you have before. If you wish to imitate an existing seal or device on the banner, you must have seen it before.
Call Upon Faith
2nd-level transmutation (Adventure domain, cleric)
Casting Time: 1 bonus action
Range: Self
Components: V, S
Duration: 1 round
You call upon your faith to grant you success. As long as the spell lasts, you have advantage on all ability checks, though not attacks or saves.
At Higher Levels: When you cast this spell using a slot of 2nd level or higher, you can target one additional creature or increase the duration by one round for each level of the slot above 2nd. If you choose to affect additional targets, each one must be within 30' of you.
Dispel Exhaustion
4th-level illusion (bard, Calm domain, sorcerer, wizard)
Casting Time: 1 action
Range: 30 feet
Components: V, S
Duration: 1 hour
You give up to six creatures creature within range a temporary sensation of vitality and refreshment. Each affected creature gains 2 temporary hit points per Hit Die and its exhaustion level is reduced by 2. It gains advantage on Constitution checks and saves. In addition, the target gains a bonus action each round that it can use to move half its speed.
When the spell expires, each target loses its remaining temporary hit points, if any, and its exhaustion returns to its previous level.
Morality Undone
4th-level enchantment (ritual) (bard, cleric, paladin, Perversion domain)
Casting Time: 1 action
Range: 60'
Components: V, S, M (a powdered holy symbol of a good deity)
Duration: 1 hour
If the target fails a Will saving throw, it becomes evil until the end of the duration. The ethical component of the subject's alignment is unchanged. The subject retains whatever outlook, allegiances and outlooks it had before, so long as they do not conflict with its new selfish and bloodthirsty outlook on all things.