Cutadapt paired end read through

You can specify this same "linked-adapter" syntax in q2-cutadapt, without it you are essentially comparing apples to oranges. Try updating your q2-cutadapt invocation to something like:

qiime cutadapt trim-paired \
  --i-demultiplexed-sequences demux-paired-end.qza \
  --p-adapter-f 'GTGARTCATCGAATCTTTG...GCATATCAATAAGCGGAGGA' \
  --p-adapter-r 'TCCTCCGCTTATTGATATGC...CAAAGATTCGATGAYTCAC' \
  --p-cores 2 \
  --o-trimmed-sequences trimmed-seqs.qza \
  --p-discard-untrimmed \
  --p-overlap 10 \
  --p-minimum-length 50 \
  --verbose \
  --p-error-rate 0.13 \

Take a close look at the command above, I edited several things, including the parameters used, and also, your adapter pairs didn't appear to match between your standalone cutadapt and q2-cutadapt invocations.

Anyway, please give that a shot and let us know how it goes! :t_rex: