** Help ** Need to filter same result but in different formulas dependent on Quarter

For Formula 1 (for UK, IT, etc. based on Q1'25):

=TEXTJOIN("; ", TRUE,
    FILTER(
        Catalogue!$B$3:$B$987 &
        IF((Catalogue!$L$3:$L$987 = E$1 & "+"), "Q1'25+", "") &
        IF(Concat!$B$1 = "XXX Group",
            IF(TRUE,
                IF(Catalogue!$M$3:$M$987 = "Y", " UK", "") &
                IF(Catalogue!$O$3:$O$987 = "Y", " IT", "") &
                IF(Catalogue!$Q$3:$Q$987 = "Y", " DE", ""),
            ""),
        ""),
        (Catalogue!$A$3:$A$987 = $D$1) *
        (Catalogue!$C$3:$C$987 = $D2) *
        IF(Concat!$B$2 = "POR",
            (Catalogue!$F$3:$F$987 = "POR"),
        IF(Concat!$B$2 = "POI",
            (Catalogue!$F$3:$F$987 = "POI"),
        IF(Concat!$B$2 = "Both",
            (Catalogue!$F$3:$F$987 = "POR") + (Catalogue!$F$3:$F$987 = "Both"),
        TRUE))) *
        IF(Concat!$B$1 = "Superset",
            ((Catalogue!$J$3:$J$987 = E$1) + (Catalogue!$J$3:$J$987 = E$1 & "+")) *
            (Catalogue!$I$3:$I$987 = "Y"),
        IF(Concat!$B$1 = "XXX Group",
            ((Catalogue!$L$3:$L$987 = E$1) + (Catalogue!$L$3:$L$987 = E$1 & "+")) * (Catalogue!$K$3:$K$987 = "Y"),
        IF(Concat!$B$1 = "XXX UK & ROI",
            ((Catalogue!$N$3:$N$987 = E$1) + (Catalogue!$N$3:$N$987 = E$1 & "+")) * (Catalogue!$M$3:$M$987 = "Y"),
        IF(Concat!$B$1 = "XXX IT",
            ((Catalogue!$P$3:$P$987 = E$1) + (Catalogue!$P$3:$P$987 = E$1 & "+")) * (Catalogue!$O$3:$O$987 = "Y"),
        IF(Concat!$B$1 = "XXX DACH",
            ((Catalogue!$R$3:$R$987 = E$1) + (Catalogue!$R$3:$R$987 = E$1 & "+")) * (Catalogue!$Q$3:$Q$987 = "Y"),
        IF(Concat!$B$1 = "XXX CHOPS",
            ((Catalogue!$T$3:$T$987 = E$1) + (Catalogue!$T$3:$T$987 = E$1 & "+")) * (Catalogue!$S$3:$S$987 = "Y"),
        IF(Concat!$B$1 = "Omux",
            ((Catalogue!$V$3:$V$987 = E$1) + (Catalogue!$V$3:$V$987 = E$1 & "+")) * (Catalogue!$U$3:$U$987 = "Y"),
        IF(Concat!$B$1 = "Letxof",
            ((Catalogue!$X$3:$X$987 = E$1) + (Catalogue!$X$3:$X$987 = E$1 & "+")) * (Catalogue!$W$3:$W$987 = "Y"),
        IF(Concat!$B$1 = "DT",
            ((Catalogue!$Z$3:$Z$987 = E$1) + (Catalogue!$Z$3:$Z$987 = E$1 & "+")) * (Catalogue!$Y$3:$Y$987 = "Y"),
        FALSE)))))))) *
        (Catalogue!$Q$3:$Q$987 = "Q1'25"),
    "None"
)

For Formula 2 (for IT, DE, etc. based on Q2'25):

=TEXTJOIN("; ", TRUE,
    FILTER(
        Catalogue!$B$3:$B$987 &
        IF((Catalogue!$L$3:$L$987 = E$1 & "+"), "Q2'25+", "") &
        IF(Concat!$B$1 = "XXX Group",
            IF(TRUE,
                IF(Catalogue!$M$3:$M$987 = "Y", " UK", "") &
                IF(Catalogue!$O$3:$O$987 = "Y", " IT", "") &
                IF(Catalogue!$Q$3:$Q$987 = "Y", " DE", ""),
            ""),
        ""),
        (Catalogue!$A$3:$A$987 = $D$1) *
        (Catalogue!$C$3:$C$987 = $D2) *
        IF(Concat!$B$2 = "POR",
            (Catalogue!$F$3:$F$987 = "POR"),
        IF(Concat!$B$2 = "POI",
            (Catalogue!$F$3:$F$987 = "POI"),
        IF(Concat!$B$2 = "Both",
            (Catalogue!$F$3:$F$987 = "POR") + (Catalogue!$F$3:$F$987 = "Both"),
        TRUE))) *
        IF(Concat!$B$1 = "Superset",
            ((Catalogue!$J$3:$J$987 = E$1) + (Catalogue!$J$3:$J$987 = E$1 & "+")) *
            (Catalogue!$I$3:$I$987 = "Y"),
        IF(Concat!$B$1 = "XXX Group",
            ((Catalogue!$L$3:$L$987 = E$1) + (Catalogue!$L$3:$L$987 = E$1 & "+")) * (Catalogue!$K$3:$K$987 = "Y"),
        IF(Concat!$B$1 = "XXX UK & ROI",
            ((Catalogue!$N$3:$N$987 = E$1) + (Catalogue!$N$3:$N$987 = E$1 & "+")) * (Catalogue!$M$3:$M$987 = "Y"),
        IF(Concat!$B$1 = "XXX IT",
            ((Catalogue!$P$3:$P$987 = E$1) + (Catalogue!$P$3:$P$987 = E$1 & "+")) * (Catalogue!$O$3:$O$987 = "Y"),
        IF(Concat!$B$1 = "XXX DACH",
            ((Catalogue!$R$3:$R$987 = E$1) + (Catalogue!$R$3:$R$987 = E$1 & "+")) * (Catalogue!$Q$3:$Q$987 = "Y"),
        IF(Concat!$B$1 = "XXX CHOPS",
            ((Catalogue!$T$3:$T$987 = E$1) + (Catalogue!$T$3:$T$987 = E$1 & "+")) * (Catalogue!$S$3:$S$987 = "Y"),
        IF(Concat!$B$1 = "Omux",
            ((Catalogue!$V$3:$V$987 = E$1) + (Catalogue!$V$3:$V$987 = E$1 & "+")) * (Catalogue!$U$3:$U$987 = "Y"),
        IF(Concat!$B$1 = "Letxof",
            ((Catalogue!$X$3:$X$987 = E$1) + (Catalogue!$X$3:$X$987 = E$1 & "+")) * (Catalogue!$W$3:$W$987 = "Y"),
        IF(Concat!$B$1 = "DT",
            ((Catalogue!$Z$3:$Z$987 = E$1) + (Catalogue!$Z$3:$Z$987 = E$1 & "+")) * (Catalogue!$Y$3:$Y$987 = "Y"),
        FALSE)))))))) *
        (Catalogue!$Q$3:$Q$987 = "Q2'25"),
    "None"
)

If that doesn't help, I recommend, like HansVogelaar, attaching a small example workbook that demonstrates the problem 🙂.

My answers are voluntary and without guarantee!

Hope this will help you.