We sing Roman Catholic hymns in the Lutheran church since you guys are our Mothership.

We even sang the classic Orbis Factor liturgy until the 1700’s in many places for our liturgy here in the United States. We share many things in common, but we were the ones who invented the chorale and four-part singing in churches in Germany and Scandinavia. It is fun to share between the two churches. We have been known as the singing church since Luther was around.
These are some Catholic hymns we sing in the Lutheran church.
Lo, How a Rose E’er Blooming
Holy God, We Praise Thy Name
Faith of our Fathers
Now the Green Blade Rises
Let All Mortal Flesh Keep Silence
You Satisfy the Hungry Heart
On Eagle’s Wings
Mass of Creation- Haugen
parts of the Orbis Factor and De Angelis liturgy Masses
Richard Proulx’s liturgy
I Bind Unto Myself
The King of Love My Shepherd Is
There are several I noticed in a Missal and
Adoremus Hymnal
that are Lutheran that you are using too. Anything Bach is Lutheran.
These too…are Lutheran…
Ah, Holy Jesus
O Sacred Head, Now Wounded
A Mighty Fortress
This is the Feast of Victory for our God by Richard Hillert
Wake Awake, For Night is Flying
Now We Thank We All Our God
There are a few Lutheran ones which I think you would like that are theologically sound in both churches.
Built on a Rock
cyberhymnal.org/htm/b/u/builton.htm
And the Swedish Lutheran classic-
Children of the Heavenly Father -
cyberhymnal.org/htm/c/o/cofthehf.htm
Day By Day -
cyberhymnal.org/htm/d/a/daybyday.htm
Rise,Shine,You People!
Earth and All Stars - Lutharan Book of Worship #558

Great hymns to learn and share from both churches. We share the same words to the liturgy and creeds.