tldr:

• for sp: replace vile acceleration with damage mod (better ammo economy) (mod list below)
• if you dont have weapon arcanes, use (amalgam) serration over bane (serration is stronger than bane when without arcanes)
• if u dont have primed bane (with arcanes), normal bane is next best alternative. if you dont like bane, use a replacement from below
• if you are missing some mods, use the next best/closest alternative (ie, [Split Chamber] for galv chamber, or rime rounds for primed cryo, etc)

viable mod alternatives:
serration, bladed rounds, hammer shot ,galvanized aptitude
ㅤㅤ- serration is most consistent option here (amalgam serration works nice with this gun too)
ㅤㅤ- bladed rounds is highest possible dps (when everything is stacked), but it is weaker initially and annoying to use
ㅤㅤ- [Hammer Shot] is also viable, I think it may even be better than bladed rounds in some situations with the status chance, + its not annoying to use
ㅤㅤ- EDIT: galv ap would be the best, but it doesnt work on aoe component and is bugged on projectile component of acceltra. I dont really understand the bug, its complicated, but the tldr is galv aptitude is weak.
ㅤㅤㅤㅤ- details about bug: https://docs.google.com/spreadsheets/d/1ryemX4Y2vWy9LjuJ355bWVNuBhzLaHTTFqPeTNto9RA/edit?usp=sharing

other:

• if no primed ammo mutation just use normal one (or vigilante supplies, but its less ammo)
  ㅤㅤ- can use vigilante set on companion weapon (applies to your weapon) for extra dps
• galvanized scope is bad (dont work on aoe or slash + too hard and cba)
• set sprint as toggle (and keep it toggled on ofc) for permanent reload buff (hidden passive of [Acceltra])

guide:
shoot things

note: i dont think rime rounds is better than primed cryo even in sp because tldr +4% status -100k base dmg is not really worth it, since all it gets u is like 1 second faster to 10 viral.

note2: [Firestorm] is not really good on [Acceltra] because its a % increase to a already small aoe. 4*1.44=5.76 which is a 1.76m increase, which barely affects this guns ability to hit enemies. it can still be used for memes over bane or [Vile Acceleration], but it is not recommended.

Enjoy! :)