I'm just playing with two Sierra MC7354 and MC7455 in a LtAP (7.5) using the bottom slot and both are just showing up as "ppp-out1" interfaces, what am I missing on the config, was hopping they would show up like LTE cards

Did you ever have any luck with these? I'm getting the same thing on my wAPR using RouterOS 7.10

Did you ever have any luck with these? I'm getting the same thing on my wAPR using RouterOS 7.10

The Sierra MC7354 should work on the wAPR. But, you need to use AT commands to set the USB mode to MBIM for LTE to work. (* = see edit below) You should be able to do this via the something like the following:

For the Sierra MC7455, that's a USB 3.0 device by default. So that may not even show up as PPP if it's the 2.4Ghz wAPR since that's USB2 (while the wAPacR that is USB3).

There is an excellent write up here on setting up the MC7455: viewtopic.php?t=186137

Note: the MC7354 uses AT!UDUSBCOMP and really should work if the UDUSBCOMP=8 (to enable MBIM support used by RouterOS's LTE interface). While MC7455 uses a more complex AT!USBCOMP (and may also need AT!USBSPEED=0) to be setup...thus the article above.

* edit for MC7354...: Previously I used AT!UDUSBCOMP=7, but it's may more likely be AT!UDUSBCOMP=8. To confirm what's needed, use:

/interface/ppp-client/at-chat [find] input="AT!UDUSBCOMP=?"

...to find the correct mode number – it's the one with "MBIM" in the line with an "AT" before it from the output of the above... the number at start of line is value to use in AT!UDUSBCOMP=8 (or perhaps AT!UDUSBCOMP=7) — good idea to check this BEFORE switching on MC7354.